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3.5l V6 Engine Record

223K views 172 replies 104 participants last post by  ViolentLee 
#1 ·
How is your 3.5l V6?
Running Strong, doesn't use any oil17524.44%
Running Strong, uses some oil (<1qt in 1k miles)35649.72%
Running Strong, uses more oil than gas (>1qt in 1k miles)11415.92%
Dead & Replaced (or sold). Used no oil when alive172.37%
Dead & Replaced (or sold). Used oil when alive547.54%
 
#3 ·
My guess is the 3.5s' that were properly maintained since new have very few issues. The design was obviously flawed, but as long as the oil was changed regularly from day one, the motors will last.
 
#5 ·
:cry: I have a 2000 model with just over 64,000 miles. This is my third trooper but is the first with so many issues. I previously owned a '98 (only 30,000 miles when totaled) and '99 (under 60,000 when sold) and never had any problems of any kind. The 2000 model has been used more aggressively than the others were, including towing up to 3,000#. Over the last 10,000 miles, although the engine has run well, there have been times when traveling the mountains of North Georgia and Tennessee (no trailer but under a small load), that I have used up to 2 quarts of oil in under 500 miles!! Even under everyday driving conditions, I don't leave my house without a quart or two close at hand. My best guess is that I am using about a quart every 500 miles or so and have just recently decided to start tracking actual consumption. When towing my trailer, I can count on a quart with every gas fill up. Other issues have included a bad starter, transmission gear sensor issues (with assoicated jerking and poor shifting), and current Check Engine Light that won't stay away for more than a day. I think it is about time to trade this 'ole mule in for a new breed of stallion.
 
#6 ·
If you aren't fixated on replacing it yet, then there are a few things that you can try.

First off, go have the Check engine light codes read. Your truck is post 1995, thus it has the OBDII diagnostics.

Second, fix what it is that's causing the CE light to come on. Given your current symptoms, I'm going to guess that you'll get a low EGR flow code. This can cause the high oil consumption as well. So, the first step is to clean the EGR valve, and passage. You can remove the EGR valve with the engine cold by removing the two bolts that hold it in. Clean it as best as you can with a can of sensor-safe carb/intake cleaner. Then clean in the EGR passage (where the EGR valve mounts). You should be able to see the EGR passage by removing the plastic intake tube and opening the throttle plate. The EGR tube is on the bottom of the intake, right inside the throttle plate. Personally, I'd clean it from both ends until carb cleaner comes out of the other end.

Spend $4 on a new PCV valve. This mounts to the driver's side valve cover and takes all of 1 minute to replace. It pops into a rubber gromet in the valve cover and has a hose that fits over the end of it. Buy a new one and you'll easily be able to locate the old one if you don't know where it is.

Lastly, you can use some engine oil cleaner just before your next oil change. Some members have used Seafoam, and others have used Auto-RX. Seafoam is typically a quicker acting treatment, and you won't have to wait 3,500 miles to see if it worked.

Good luck, and let us know what is causing the CE light to come on.

-Tad
 
#7 ·
Tad said:
If you aren't fixated on replacing it yet, then there are a few things that you can try.

First off, go have the Check engine light codes read. Your truck is post 1995, thus it has the OBDII diagnostics.

Second, fix what it is that's causing the CE light to come on. Given your current symptoms, I'm going to guess that you'll get a low EGR flow code. This can cause the high oil consumption as well. So, the first step is to clean the EGR valve, and passage. You can remove the EGR valve with the engine cold by removing the two bolts that hold it in. Clean it as best as you can with a can of sensor-safe carb/intake cleaner. Then clean in the EGR passage (where the EGR valve mounts). You should be able to see the EGR passage by removing the plastic intake tube and opening the throttle plate. The EGR tube is on the bottom of the intake, right inside the throttle plate. Personally, I'd clean it from both ends until carb cleaner comes out of the other end.

Spend $4 on a new PCV valve. This mounts to the driver's side valve cover and takes all of 1 minute to replace. It pops into a rubber gromet in the valve cover and has a hose that fits over the end of it. Buy a new one and you'll easily be able to locate the old one if you don't know where it is.

Lastly, you can use some engine oil cleaner just before your next oil change. Some members have used Seafoam, and others have used Auto-RX. Seafoam is typically a quicker acting treatment, and you won't have to wait 3,500 miles to see if it worked.

Good luck, and let us know what is causing the CE light to come on.

-Tad
Tad, You might want to advise folks to only pull out the PCV valve while holding the grommet in place, otherwise the end of the grommet inside can break off and float around inside the valve cover.

It's also a good idea to replace the grommet at the same time as the PCV valve.
 
#8 ·
k2c3m4 said:
Tad said:
If you aren't fixated on replacing it yet, then there are a few things that you can try.

First off, go have the Check engine light codes read. Your truck is post 1995, thus it has the OBDII diagnostics.

Second, fix what it is that's causing the CE light to come on. Given your current symptoms, I'm going to guess that you'll get a low EGR flow code. This can cause the high oil consumption as well. So, the first step is to clean the EGR valve, and passage. You can remove the EGR valve with the engine cold by removing the two bolts that hold it in. Clean it as best as you can with a can of sensor-safe carb/intake cleaner. Then clean in the EGR passage (where the EGR valve mounts). You should be able to see the EGR passage by removing the plastic intake tube and opening the throttle plate. The EGR tube is on the bottom of the intake, right inside the throttle plate. Personally, I'd clean it from both ends until carb cleaner comes out of the other end.

Spend $4 on a new PCV valve. This mounts to the driver's side valve cover and takes all of 1 minute to replace. It pops into a rubber gromet in the valve cover and has a hose that fits over the end of it. Buy a new one and you'll easily be able to locate the old one if you don't know where it is.

Lastly, you can use some engine oil cleaner just before your next oil change. Some members have used Seafoam, and others have used Auto-RX. Seafoam is typically a quicker acting treatment, and you won't have to wait 3,500 miles to see if it worked.

Good luck, and let us know what is causing the CE light to come on.

-Tad
Tad, You might want to advise folks to only pull out the PCV valve while holding the grommet in place, otherwise the end of the grommet inside can break off and float around inside the valve cover.

It's also a good idea to replace the grommet at the same time as the PCV valve.
That is sound advice.

In case you don't have an Isuzu dealer nearby that's still in business:

Someone wrote earlier that they had found the grommet at Autozone...here's the info I wrote down from that post:

Ford/Mercury Motormite 42330

-Tad
 
#10 ·
Definitely a flaw in engine design. Mine did not use(or use minimal) oil probably until 60k(which coincides with my 5.38 gear swap - motor now runs about 3k rpm at 72mph).

I've had the dealer clean the egr/tubing during an IMG replacement at 130k;pcv is working normal. I have checked the EGR/pcv myself since and found them working fine. Also used Auto-Rx, etc but the consumption stays or have gotten worse(definitely needs to check oil level every other gas fill up and always carrying a quart). I might try to pour seafoam or lube control to each cylinder to try to clean the rings but some folks have already done this and pretty much did nothing as well. I have also experimented with different weight/brand of oil but to no avail.

I am keeping this truck till the end tho. Everything runs good other than the oil consumption(and price of oil is way cheap compare to a new truck).
 
#11 ·
Thanks, Tad, for the info above but I had already done most of those items because of the "low flow" code. In addition, I have replaced the fuel filter, and replaced the spark plugs with OEM Denso's, but the CEL remained on. This morning, for the first time in about a week, the truck cranked fine and the CEL went off after a few minutes of driving. This is the first time that the CEL has gone off without me resetting the ECM/ECU. Go figure... all the checks, replacements, and cleanings, and the light goes off on its own. Maybe I sprayed tooooo much carb cleaner while cleaning the EGR. I drove the car over the weekend for about 200 miles, even with the CEL, and maybe I just blew out some of the old cobwebs. Wish I knew... Thanks again for the help but the CEL is off for now. I will again begin to track the oil consumption to see if I can detect a change there as well.
 
#12 ·
I bought a '99 Trooper about a month ago. It is the 3.5L performance package, with 95k miles. I drove to Florida, and used over 2 quarts of oil. I am using at least a quart every 500 miles or so. From reading some of the postings here, I guess I'm not the only one with this problem.

I'm going to try switching to full synthetic oil, as well as cleaning the EGR valve, and replacing the PCV valve. Has anyone had any luck using a heavier weight oil, and if so, what is the heaviest weight I can use?
Also, do oil additives like Slick 50 or Lucas work?

Overall, I'm very happy with the Trooper, but I just can't believe it can be using this much oil. There don't appear to be any leaks, and the tail pipe is black, so I guess the motor must be burning it.

I would appreciate any help or advice. Thanks.

Simon.
 
#14 ·
Well I have my own opinion on this as my 2000 Trooper is sitting waiting for a new, used motor. Since I cannot drive anywhere I have had lots of time to do research. Here is just a sample of what I have found -

Jeff of Grand Prairie TX (9/14/04):
I own a 1999 Isuzu Trooper with around 67,000 miles on the odometer. I and my family enjoyed the vehicle until about 6 months ago when, on a 250-mile run from San Antonio to my home, I experienced a loud whining and everything lit up like a Christmas tree and the truck went dead. After a long wait and an even longer tow, I had the vehicle checked out and was told that the engine was locked up tight as a drum and that there was just under 1 quart of oil in the pan.
During my ownership of the truck, I had noticed that the dipstick would occasionally and unexpectedly read low - and it never visibly burned any oil. I have owned many classic and high performance vehicles in the past and am a stickler for maintenance. I had changed the oil in the truck around 3000 miles earlier and thought, as any owners manual will tell you, I was keeping up. My immediate thought was that the previous oil change had been done incorrectly - but my own diligence in checking the oil prior to my trip and adding a needed quart steered me away from that as a solution.
Now, after an attempt to locate a replacement engine for the truck online, I find that I'm not alone by any means. Being out of warranty (just) leaves me with the belief that I will just have to eat the cost of getting the vehicle back on the road, but I feel that, given the number of similar stories out there, Isuzu should pony up and assist those who can prove their stories.
My truck is currently being re-diagnosed and repaired after a $285 tow. Initial estimates have indicated that I will likely be out around $3000 for the engine plus several an additional $1000-$2000 in labor.

Robert of Stoughton WI (12/30/03):
We purchased a 1999 Trooper, 3.5 ltr. new in November, 1999. We had the oil changed on a regular basis per recommendations. At the last oil change (October, 2003), Valovine indicated that there was no oil in the motor. We just thought that they had not filled it up properly the last time the oil was changed. At that time, there was less than 60,000 miles on the vehicle. We drove from Wisconsin to Ohio for Christmas which is approximately 580 miles one way. On the way back, the oil light came on in Chicago.
We stopped and put in 2 bottles of 10W30. The oil did not register on the stick. We continued home. We checked the oil when we arrived home and it was not registering again on the stick. We added oil again. The mileage on the vehicle is now 62,000 miles. We contacted Zimbrick's Service Manager and they basically said that the warranty is out and we will need to replace the engine.
Isuzu has known about this problem which occurs in the 1998, 1999 and 2000 3.5 liter vehicles. They corrected the problem with the later 2000 vehicles. It is occuring after the warranty expires in most cases. They did not notify us to indicate there might be a problem with oil consumption. If they had, we would have taken it in after the oil change prior to the warranty expiring. I think Isuzu should back their product. Our vehicle is only 2,000 over the warranty and it was an existing problem that we were not aware of.
We may have to replace the engine, which would cost more than what the vehicle is worth. We still owe one year of a five-year loan, approximately $4,000.00. It would be stupid to replace the engine and incur $6,000-7,000 in expense for a vehicle that isn't worth that.

Toynie of Palm Coast FL (11/25/03):
In October of 1998 we purchased a 1998 Isuzu Trooper with a 6-year or 100,000 mi. extended warranty. It was not until the fall of this year when my husband was returning from the beach with our three-year-old daughter and the motor blew up that we found out it was underwritten by Smart Choice and that the company was now bankrupt. Then we found out that we would have to pay in the neighborhood of $3,000 to $6,000 for a new motor.
etc. My engine seized on me on the way back from a trip. There are no oil leaks or anything that would indicate a problem. I now need a new long block on a perfectly good truck. This is major money. Thanks for listening.

Joseph of Shreveport (1/28/03):
I own a 99 Isuzu Trooper. I bought it new. In November 2002, as I was headed out of town my oil light came on. I immediately stopped the vehicle and popped the hood to see what was going on with my oil. I checked the oil stick and found that it showed the oil level as full. I got back in the vehicle and drove about a mile.
Suddenly, I heard a loud rumbling sound coming from under the hood. The dashboard lit up, and the engine went dead. I pulled off to the side of the road, looked under the hood and could smell something like burning rubber. When tried to restart it nothing happened. Later, I had it towed into the dealership, which said it looked as if the engine blew up. He stated that it could cost as much as $12,000 to have the engine rebuilt. He knew of a used one that he could get for about $5,000 and that it would cost a total of about $7,100 including installation.
Of course, I had no way of coming up with that kind of money. I later found a number from the internet to the Isuzu manufacturer. It took me forever to speak to someone and when I did they offered no help at all. They were only concerned that the warranty had gone out and were under no further obligation. This vehicle has a 60,000-mile warranty; I had about 76,000 miles on it when the trouble happened. To say the least, I am very disappointed with Isuzu. This is my third Trooper I've purchased from this dealership. I thought that would have counted for something.

Amy of Fort Worth, TX writes (10/26/02):
Purchased a 1995 Isuzu Trooper in 1997. The engine went out 3 months ago. No engine to replace it can be found and in our looking for an engine we discovered that this model Trooper had a known wrist pin problem in the engine and that is why we can't find one today to replace it. Even if we did find one the same problem would happen so why would we buy an engine new or rebuilt just to have it do the same thing? One rebuilt engine we found was $4500 plus shipping plus installation from a mechanic. I think that is absurd when in any other NEW car you can get a new engine for that much if not less. Isuzu won't help us and claims they "know nothing" of this problem. I say BS.

Pamela of East Bridgewater, MA (8/19/02):
I purchased at the end of my lease a 1997 Isuzu Trooper. I felt I was the only owner and it only had 36,000 miles on the car. I haven't had any real trouble with the car. I have taken care of the car with oil changes, rotating the tires, tune-ups, etc. Well then my car begins to make this horrible wrapping noise and smoking. I called the dealer and they said they couldn't look at the car for at least a week. I need the car for transportation back and forth to work. I found another reputable mechanic that used to work for the dealer and now owns his own shop.
After doing a diagnostic test on the car he explained that it needed an oil pump. I spent $1100 for this job. After picking up the car it began to make other noises. I asked what this was and he stated that it sounded like the lower portion of the motor. I wanted to make sure that he was right so I made an appointment to have them diagnose the problem and confirmed the problem. I asked if there was anyone from Isuzu that I could speak to about this and they stated that the service manager would need to speak to the Isuzu factory representative. He stated that he would do this on Monday of the following week. I called the service manager to remind him and he placed me on hold for approx. 3.2 minutes and came back with a flat no. Isuzu is not responsible and I am out of warranty so basically thanks for nothing.
I tried to contact the customer service department to get this individuals number so that I could advocate for myself the situation and possibly explain my situation. But again I was told that the service manager would speak on my behalf. I feel that a car motor should last more than 71,000 miles and that I will make sure that I never purchase or my family will never purchase or anyone I can possibly talk out of purchasing an Isuzu vehicle.
I have three children and they are beginning school in a couple of weeks. I had to spend $1100 and then be told the motor is no good. I wasn't looking for a free ride but I am looking for some help. I was never offered at the end of my lease an option to purchase an extended warranty. If I was I would have it to cover me in situations such as this.

Howard of Chicago (6/5/01):
I own a 99 Isuzu Vehicross [same engine as the 99 Trooper] with 35,000 miles. Last month the engine seized, and apparently needs to be replaced. Although the warranty is still in effect, Isuzu refuses to honor it. They say I have to document oil changes every 3000 miles and should've checked the engine oil level every other time I filled the gas tank. My limited search on the web has revealed that numerous Isuzu owners with V6 engines have unexplained engine oil loss. Isuzu knows about this but refuses to do anything to warn consumers except a single line in the owners manual about checking the oil every second gas fill-up. The oil warning light also does not warn of loss of oil. Isuzu wants $6500 cash to replace the engine

. . . and last but certainly not least . . .

From a Better Business Bureau posting
Have you had engine failure problems with your Trooper?
My 1999 Isuzu Trooper is on its fourth engine. After complaining of excessive oil usage in my first (a 1994) Trooper, and being told it was normal, a wrist pin in the engine failed at 110K miles. Isuzu would do nothing, but the dealer moved me into a new '99 Trooper.
I watched the oil consumption very carefully with dealer documentation. At 57K miles they agreed it used too much oil and Isuzu put a new long block in the vehicle. The oil consumption dropped to nearly nothing and the engine seemed fine.
At about 45K miles on the new engine, and while driving on the Interstate at 70 mph in cruise control, the engine came apart with no warning. Pistons and rods went through the side of the block and out the bottom of the oil pan. It turns out that Isuzu only warranties their replacement motors for 12K miles -- not the 60K plus they cover in the original equipment motors ?!?!
Isuzu would do nothing about this and I ended up putting a new motor in at the cost of $7500. The dealer actually had to put in a second long block because the first one came apart when they started it!!!!!!!

This morning, with less than 6K miles on this new engine a metallic noise started in the engine. It is at the dealer's now and I dread the outcome.

Back to my Trooper again. I am still waiting for the used engine of which there are none because they are all used up as replacements!

We all need to face facts. These things are junk! The company is will not support its customers. We all need to find a new marque to support - one that works, with a manufacturer that supports us !!!!!!!
 
#15 ·
On the way back from Moab yesterday mine blew. Oil was fine when I left, when the engine downshifted about 3/4 of the way home, I heard knocking and immediately pulled over. Rod knock and now I'm looking into getting a new, used engine or just scrapping this POS.

:evil: :x

:edit: found out some new info. See this thread: http://forum.planetisuzoo.com/viewtopic.php?t=4003
 
#17 ·
Correct, except that all of the DI engines are after the date that the updated design started. So it's like saying that the 3.2s are the same design as the "bad" 3.5s. The 3.2 and 3.5 are cousins just like the older and newer 3.5 are cousins (we'll call them fraternal twins).

-Tad
 
#19 ·
Hey All,
New guy with sad story: bought a 2000 trooper nov 2004 with 77k miles on it. Engine locked up with no oil on a trip to grandma's house the day after Christmas. I had no idea of the problems associated with this engine, I only had 1900 miles since the last oil change and didn't even consider any oil problems. Apparently it was going out the exhaust. Anyway, I got a used engine (21k miles) for 3k dollars and now check the oil every time I get in it. No problems so far.

wd3
 
#20 ·
Hi Tad
I have a 2002 Trooper (Holden Jackaroo in Aust). I have not noticed any oli issues, but have not looked as car is under warranty and is services every 6 months. Mine was built in late 2002. i noticed you mentioned that this problem was fixed in the later models. is this the case. i believe that my one is the last of the bunch. The last two times I have been off road, the engine warning light has come on, but gone off again on the highway on the way home. Holden have been unable to tell me the cause, so I may take notice now. this was not the oil light, only the "check engine" light. i will keep an eye on this as the car comes off warranty in 8 months.

Tom
 
#21 ·
warrenty won't cover neglect from my understanding. check your oil.
 
#22 ·
listening to this sort of stuff, makes me nervous. So was it the 92-97 years that made isuzu popular. I know a lot of people that have thost model years, and have ZERO problems. A friend has almost 200,000 on his 93 and its still got all the punch its supposed to. im kinda afraid to hit the gas on mine, wanna make it last as long as I can.
 
#23 ·
Are there any other engines, Ford, GM, Nissan, whatever, that can fairly easily be installed in my 2000 Trooper. 90,000 miles. Kind of hate to spend $3k to $6k on another 3.5L if it's going to do the same thing.

I still owe $4k, so I don't want to just dump it. If the new engine will last, I don't mind spending the money (well I do, but it's better than throwing the thing away)

I don't have the expertise, time or tools to tackle it myself, so it would have to be something affordable at a good shop.
 
#25 ·
After checking the oil at the beginning of the trip (full), and having to add a quart every, say, 1000 miles, my 98 starved on the way home (about 200 miles after reading full) at the top of a mountain pass, and burned up a piston, presumably. Rebuilt (Probilt from Pep Boys) engine, installed by small garage, found to have two missing lifter clearance tabs (Probilt's fault). Engine runs OK, has good power but is now rough, and has a check engine soon light. Frustration, frustration, frustration. I don't like checking and adding oil with each gas fillup.
 
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