Just got a red 89 trooper, 176k mi, v6, virtually no rust. Runs strong once warm, but runs like crap on start-up. I replaced the spark plug wires, checked the compression, and the plugs.

Questions:
1) Compression is about 140 in all cyl. Is this good? Haynes manual says "not available" for this spec.
2) The hood is an aftermarket replacement (it's rather flimsy, too). Can someone take a photo of the VECI and vacuum routing labels (and any others) to email or post? 89 V6, non-california truck.
3) I have no jack. Any suggestions for a cheap aftermarket
replacement? I could only find an 11" bottle jack. Too short.
4) I raised the driver's seat, but how do I lower it? (no owners manual)
5) It stalls sometimes on deceleration. I will check the fuel pressure and timing tonight, but any other ideas?
6) Check engine light sometimes comes on, but not long enough for me to pull codes. Not in any pattern that I can see so far. Ideas?
7) Is there any advantage to using premium oil (synthetics like Mobil-1) in the tranny and t-case?
8) Is there a way to tighten the vent windows so they stay put when opened?
9) What's up with these brittle plastic vacuum lines? Can I replace them with 1/8" ID hose instead?

Whew! I hope it's ok putting this all in one post, please answer if you can, thanks a million. <img src="/forums/images/graemlins/patriot.gif" alt="" />

Get a Hi-Lift! Works for wheeling, as well as changing tires. Otherwise, check EBay, or go to a wrecking yard.

Hmm can't really answer any more questions. Check your fuel filter?

When you say plastic vaccum lines? If they are just old hose that is cracking, replace them all! Vaccum hose is cheap, and does a wonder to your engine.

Congrats on the Troop BTW <img src="/forums/images/graemlins/kewl.gif" alt="" />

On the seat, you have to sit on it while you turn the handle. I think there is a spring or something that you have to go against.You can lower it without sitting on it, but its hard. I tried all kinds of stuff to get the vent windows to stay open. The only thing i got to work, was to put a strap with velcrow (sp?) and strap it open.
And you can use some hose with 1/8" ID. I hope that helps some! And the factory jacks not that great, i would try to find something better. <img src="/forums/images/graemlins/cheers.gif" alt="" />

There's vacuum lines that are, well, PLASTIC. They are super fragile, I broke one while pulling #1 spark plug.

Oh, and re: the VECI label, it's a 5 speed. I need the VECI for timing and idle data. Thanks again.

The timing says 10* btdc, under 1000rpm. And the idle speed is 800 rpm. hope that helps, and welcome to the wire. <img src="/forums/images/graemlins/cheers.gif" alt="" />

I replaced the fuel filter. Will check timing tonight. The stall-on-deceleration problem is apparently gone, now it idles (after the rough warm up time) at 2500 rpm! I only have a homemade fuel pressure gauge with rubber hoses, so I couldn't attach it to the fitting at the throttle body to test pressure. The Hayne's manual says there's no procedure to adjust idle (controlled by ECU?), is there a screw to adjust for a baseline idle setting?

umm... there SORTA is, but you don't want to mess with that.

do a forum search for reset IAC and you'll be fine.

Pull out the front tray of the console between the front seats. Under there should be a rectangular connector with only about two actual connectors (maybe three). One is labeled A and the other is labeled B. Take a thin wire a few inches long and strip off the insulation from the ends, about 1/4" (I used an old twist tie). Jumper A & B and then turn the ignition to the on position.

You should then get the engine light to flash the error codes it has stored in the ECM. The codes always begin and end with 12 (long flash followed by two short flashes). So, 12 then whatever other codes, then 12 again when it is done. Then, the flashing will start all over again.

There are several websites that list trouble codes. I don't recall any off the top of my head, but do a search for +trouble +codes +web or something like that.

HTH <img src="/forums/images/graemlins/kewl.gif" alt="" /> <img src="/forums/images/graemlins/kewl.gif" alt="" /> <img src="/forums/images/graemlins/kewl.gif" alt="" />

Do a search for +transfer +case +fluids, if I remember correctly the txfr case and tranny use regular engine oil. In fact, the fill plugs have Engine Oil stamped on them. When I changed mine I just used dino oil, but I added Lucas manual tranny additive. FWIW, Lucas products work great, in my experience.

One note- make sure the new oil is room temp if possible. I changed mine back in Feb and the Lucas got cold and was a pain to pump into the tranny...

Not too long ago I replaced the ECM om my '89 Trooper with the 2.8 engine. Prior to replacement I could not retreive trouble codes, and the EGR system was not working. The new ECM cured both problems. I'll paste in the instructions for getting trouble codes. Can't remember where I got this, but it works well. If you lift out the two trays between the front seats, you'll find the ECM, and there should be two wires there to connect for the test.

******************

THROTTLE BODY FUEL INJECTION

The ECM test connection is located under the center console.

A built-in, self diagnostic system will identify problems most likely to occur in the throttle body fuel injection
system. When a problem is detected, the diagnostic system will illuminate the "Check Engine" lamp in the
instrument panel.

When the engine is started, the Check Engine lamp should turn oft. If the lamp remains lit, the self diagnostic
has detected a problem. To determine where the problem exists, ground the "Test" terminal of the connector with
the ignition On, engine Oft and observe diagnostic trouble code display. Each DTC will flash three times in
numerical order (lowest to highest). Each diagnostic trouble code will indicate a fault in a particular circuit.

MULTI-PORT FUEL INJECTION

Amigo, Pickup, Rodeo & Trooper II

On Amigo, Pickup and Rodeo (except 1993-95 models W/3.2L engine), connect the single wire diagnostic leads
located behind the left hand kick panel together. On Trooper models to 1991, the single wire diagnostic
connectors are located under the center console. On 1992-95 Trooper & 1993-95 Rodeo models W/3.2L engine,
connect a jumper wire between data link connector terminals 1 and 3. On 1992-95 Trooper models the data link
connector is located behind the lower front of the instrument panel. On 1993-95 Rodeo models W/3.2Lengine,
the data link is located under the left hand side of the instrument panel. On all models, turn the ignition switch to
the On position. At this point, the "Check Engine" lamp should flash.

********************************

That doesn't look too good on my screen, but the information is there. Somewhere I have pictures of the ECM and associated wires, if you need. Remember, the 2.8 engine is a GMC engine, just as found in any number of GMC vehicles.

HTH,
Ken