Comments: 1-15, 16-24
Aluminum heads either cracked or blew gaskets three times within 40K miles, and this was without overheating problems according to a temperature gage, water pump, and radiator that were all found to be in working order.
Granted, I got this car with a lot of miles already on it, and I got it for a very good price -- or so I thought. Every mechanic I know and trust says the same thing about the 4-cylinder, 2.6 liter motor, "they're underpowered and thus problematic." Its always the same problem, cracked heads or blown head gaskets due to the combined traits of being too small a motor in a large vehicle AND expecting it's aluminum head to handle the task. Honest mechanics have even declined to rebuild it for me because they know its reputation. These are good guys whom I know.
Good side, relatively economical for an SUV with a heavy four wheel drive transmission to tote around. Averaged 18 miles per gallon in city, 22 highway.
Excellent visibility, view in all directions.
Classic 'box'-y design still looks good after many years. Notice lately Mercedes and Toyota have brought out extremely box-y new 4x4 models.
The automatic transmission has a good reputation. Even if it slips a little or is sluggish to awake on cool mornings its really not going out! I know this from both my '88 and '89 Troopers, both in the 175,000-215,000 mile range. Just do a simple transmission filter change. I've even talked to transmission shop owners about this, they've told me they almost never have to fix '88 or '89 Trooper II automatic transmissions.
I've also heard good reports on the '90 and '91 V6 motors from mechanics who rebuild engines. Apparently here in the states it used some American auto maker's motor (was it GM?).
Yes, the V6 engine used in 90-91 Troopers is indeed none other than the old reliable GM 3.1 liter. A friend who owns a Trooper with the V6 says that the power is great and gas mileage is not too bad either. The engine can supply enough torque that there is no need for an overdrive lock-out button like the four cylinders have.
He did comment on the problem he has with rough idle on cold start, but added that it smooths out when warm. This year engine used the GM E2SE style carburetor and I wonder if the upper end of a newer, fuel injected V6 out of a GM car would work if one could overcome the obvious problems adapting transverse heads to a longitudinal block.
I have often wondered what installing a 3.8 liter GM V6
would involve... Or even the 4.3 liter truck engine?
2.8 gm's went in the troopers until they were replaced by the isuzu 3.2. some rodeos of that era had the 3.1 gm. not many. you can't bolt a 4.3 up to an isuzu transmission. you have to use a true v-6 gm--not a small block 8 with two cylinders removed... like the 4.3. most people swap in a 3.4 out of a camaro.
Regarding heads/head gaskets on the I-4 isuzus: if you keep your valves adjusted, your cooling system operating properly, and you don't beat on your rig, you should have good luck. all of the failed heads and head gaskets I've seen had several things in common. poor maintenance and abuse. some of the earlier head castings were suspect, but I've got one with 233,000 miles on it going strong. I take care of my vehicles. I adjust the valves every 15,000 and change the thermostat once a year when I'm doing my flush and fill on the radiator. additionally, I've never seen a stouter bottom end on a 4 cylinder. that block and crank are beasts!
I own an 88 trooper II, now with 289,200 miles on it.
Great torque and power at the slower speeds, but going from 45 to 55 you have to be a little patient.
I'm not out to beat anyone off the line, but I have used it to pull a 16 passenger van and a Chevy Suburban out of the mud with, 4x4 low is great.
My problem right now is the oil pressure readings.
I don't know if it's the gage, sending unit or the pressure.
At idle the pressure reads 45-55 psi. That may hold as the RPM's come up or may not. The real reading drop usually occurs at higher RPM's 2000 - 3000 for extended periods, but not always.
The gage reading may fluctuate from near zero to 55 at the same RPM's.
Sometimes on the highway when the pressure drops, if I drop out of gear and let the RPM's come down the pressure will come back up.
I change the oil regularly and check the level constantly.
I'm thinking about a used motor to rebuild and swap.
Any hints or input would be greatly appreciated.
I would go for the rebuild kit. There are many out there. Look @ ebay. They have good buys for the money.
I own a 88LS just got it a week ago had to fix the ECU, and now doing a head job will send pic's if any would like to see. my dad has 89 and I've never seen a better SUV for the outdoor world makes jeep look cheap. (lol) But these trucks hold there own. Like you said if you don't stay on top of them they can get alittle temperamental. But that's life. e-mail for any tech info or?'s about mods
mhof422334@yahoo.com -Matt.
I have a 1989 Isuzu Trooper II 4x4 with a 2.6Lt gas engine and 5-speed manual transmission that my daughter and husband gave me about a year ago for a Buick Century I had, but did not use much. After doing some things that had been let go I have had very satisfactory results. A mechanic had disconnected the smog pump and removed the drive belt and I have not replaced that yet. I am wondering if that might improve or make my mileage better. Currently I am getting about 20MPG on the highway. I have had it stuck in mud, but that may be the tire tread design more than anything else, but then it does not have a traction lock differential either, which I would like to have. I just carry a winch along on off road trips. I don't dog the engine and do not pull heavy loads more than a couple miles. I do town my Trooper behind our motor home and had to experiment to learn how to disengage the steering wheel lock so the front wheel would turn while being towed
I have an 88 trooper II with the 2.6 liter engine. I had a long block put in the trooper after the crank bearing went out. The vacuum lines were not hooked up completely. I am looking for some photos (digital is fine) of proper connected vacuum lines. My email is kyleh200@yahoo.com. I need photos for the intake related lines the more the better :-)
I've also got an 88 trooper with the 2.6L and get 19-22mpg consistently. I've done absolutely nothing to it for 215,000 miles except typical oil changes, tires, timing belts and a couple of fuel pumps. Love it and am trying to keep it forever...but...Just moved to AZ and since moving here it seems that whenever it is above 105 degrees, after about 30-40 minutes of driving it sputters and then quits. I sit on the side of the road for a few then start back for another 5 minutes or so and same thing happens... Come back the next day and it's the same thing.. unless it's less than 100 then I can drive all day no problems...
Re trooper in AZ. have you checked your gas cap? I moved from WA state to Las Vegas, and when my tank was low and it was hot out (over 105*) it would vapor lock and die. since your post was written in July, now sept, you probably found the culprit, if not try a new gas cap they are a cheap try.
I am rebuilding a 92' Amigo 2.6 4x4. Using parts from Calmini including header, camshaft, and high compression pistons (10:1) @.20 overbore in hopes of close to 200Hp
As for the head cracking, some friends and I have rebuilt his 2.6 in a pickup truck with a cracked head (#3) and drilled out the coolant passages in the gasket. This seems to have helped quite a bit, also running a low temp thermostat. No problems in 3 years.
The problem with the 2.6L 4 is not the engine it isthe catalytic converter. I had the same problems as noted by the readers and went through 2 heads and one engine before I got the scope. A engine rebuild company owner said that it is heat build up due to a clogged catalytic converter. This was much like what was going on in big block GM motor homes, which had a small diameter exhaust, and in turn caused all kinds of problems until they increased the diameter of the exhaust. The 2.6 L 4 is a great engine and will run the 6 into the ground. It will pull you up anything that if you can get grip. Fixed the converter and all is well.
It had me going for sometime --- R. King.
My 1988 Trooper II 2,6 liter started sputting, had a compression test performed, found the first and second cylinders had between 25-45 psi. What causes this problem?
My wife tells me not to invest in it, while it was running it was good on gas and great vehicle in the winter times, especially here in Colorado. Looking for input. Thanks.
I have an '89 Trooper with the 2.6 four and a five-speed. I think it's an amazing four cylinder! It has a lot of torque, and I can't believe the.2 liter increase in the six could much improve on it. I'm reasonable about my maintenance and upkeep, but it sometimes goes a bit longer than it ought to because I put a lot of miles on it as a work truck and don't always have time to change the oil, etc. every three to five weeks (3K miles). Even then, and with hauling a cargo area full of heavy tools, it's been a great vehicle!
And I don't baby it! I'm not afraid to push it up to 5000 RPM between shifts to get into traffic, and have also driven it home on I-25 from jobs late at night with the speedometer pegged --- maybe 115MPH? I'm amazed how stable it is at high speed on the highway even though it feels so light and nimble at low speeds and off road.
It's also the best vehicle I've ever driven in the snow, and I've been driving 4-wheel drives for years. I thought my Toyota T100 couldn't be beat, but now know that the Trooper beats it. It's a boxy, kind of buzzy, utilitarian ride, but I really like the little thing. If I kill it (and it has 232,000 miles now) I'm sure I'll either rebuild it or buy another one --- probably rebuild... and with the Calmari high performance kit and header and all of that. I mean, the thing even has wing vents! How many cars can you find with wing vents anymore?
I just picked up an 88 Trooper II with a blown engine. I have a doner S10 Blazer with a 4.3. Has anyone ever heard of swapping the whole drive train, engine, tranny & TC? How do the mounts match? Issues with computers?
I bought a 1988 Isuzu pickup from a friend who had put 435.000 miles on the original engine. After rebuilding the engine with no more than ten thousand miles on it, I had to replace the head with a new one (old one cracked due to heat). It began to have a problem with leaking coolant (very slow first several thousand miles then progressively worse, was burning it through 3rd cylinder) Could not figure out how a fresh engine could have this problem.
Well now I know what happened. When you fill a 2.6 Isuzu with coolant for the first time after emptying the block, it does not allow the coolant to enter the block and head. I started engine with new head yesterday and ran it maybe five minutes waiting for temp gauge to move, it would not. Then I remembered the first time I ran it after engine overhaul, (about two and a half years ago) the same thing happened, but that time I drove it after several minutes idling and when the thermostat finally opened (from hot air I assume) the gauge climbed to about two thirds very fast.
I have never seen an engine that did not have a bypass to allow the coolant to get to the head and block. After realizing what was happening I took out the thermal valve just behind the thermostat and started the engine.
After I saw coolant spraying out I put the valve back and filled the radiator back up, it held about a gallon more coolant after purging air from the block. I Think what happened after rebuild is that the engine got hot slightly warped head creating slow coolant leak into #3 cylinder and small compression leaks from cylinder to cylinder (from looking at damage to old head gasket) After about 900.00 dollars in parts and a ridiculous amount of wasted time, I know how not to warp and crack a cylinder head and blow a head gasket on a 2.6 Isuzu engine; simply take out the sensor behind the thermostat and fill the block with coolant through the sensor hole, then fill radiator and everything will be fine.
This is what I will do next time (3rd time) I expect that the same thing has happened again, but am hoping that it has not. Good luck.
I own a 1989 Trooper with the 2.6 engine. Had the head / top end worked over a couple of years ago, but the bottom end is still original. It has about 139,000 on the odometer. Coolant level is still good; hasn't really changed since summer.
Lately, the temp gauge reflects that the engine is running cooler than it did this past summer when the needle climbed to a bit beyond halfway on the gauge, but now it barely registers a quarter of the way across.
Don't know what is happening here, but the engine runs smooth, burns a bit of oil, and there is loads of torque.
It's a 5-speed manual, I'm the original owner.