Is there anywhere I can get a definitive layout for ALL vacuum hoses? I
have seen the few pics on planetisuzoo.com but it leaves a lot out,
still... I just got my 88 and found a lot of hoses needing replacement
and during this, I have found a lot that are not hooked to anything.
When I used the aforementioned planetisuzoo pics, I followed what I
could but now I get a good start and then id shuts off. Cannot keep it
running at all. It WAS just having an issue with not wanting to start
when the engine was hot, now the symptoms have spread. I really want to
think that both issues are vacuum-related, but I cannot find much out
there for routing...

Please help!!

Thanks!

I think those pics on planet that you're talking about are some I took of my truck for a kid named Adam in Florida. He's the one that posted them on planet. If it would help, I'd be willing to take some more pics if you can tell me what areas you would like to see.

Here are the original pics I took for Adam. Vacuum Line Pics (http://pws.ecarthage.com/nivens/adam/)

Hmmmm, three days ago, same exact post over on 4x4 wire... pics were offered... never replied ... oh well.

Thank you for the offer (both places) I found a car lot around the corner that had a 90 that I nabbed some pix of, it woul have been really really difficult for me to remotely tell someone what I needed pics of. Thank you again for the offer, though... I have it running now, just with an odd occurence... it is starting and idling for about two seconds and dying, like it has no fuel. I turn the key to acc to run and hear the fuel pump prime then go to start, it fires and runs and dies. I can give it throttle and bring the revs up and then as it is dying, bump the key from acc to run a couple of times (like to pressurize the fuel lines) and it will go to idling fine, no further dying. It is like the fuel pump is not getting power for a few seconds during the change from running from battery to running from alternator. or something... I know I am not giving a really good description, but I am not sure how else to explain it.

also, I am seeing (as it idles) a few random bubbles in the radiator puke-tank... might that mean head-gasket woes are approaching? Is replacing the head gasket and timing belt a good preventive measure? I think the h/g was done about 20k miles ago... as I do this, what else should I do (while it is taken apart and such...)

thanks!

No sweat, just thought it was curious that you asked, then disappeared! :shaking:

Glad you found the info that you needed...

I have heard similar problems, I think it may have something to do with the fuel pump relay... your alternator could also have low output, if I recall what I've read on the subject. Something about the fuel pump circuit switching from the battery (starting) to alternator (running) power. Search the archives here and on 4x4 wire, I know it's been explained better than I can!

If yer seeing bubbles in the "puke tank" I think it might mean that head woes are not "approaching" but already there! When they replaced the gasket 20K ago, do you know if the head was checked for cracks ? VERY common for these engines.

I just got done putting a new head on mine, and one of my first clues was the bubbles in the "puke tank" ... also had loss of coolant, but don't trust the level in the tank as an indication of the level in the cooling system. Wait till the truck cools, and open the radiator. My round trip to work and back is about 16 miles, and I was losing about a quart of coolant a day, that DID NOT show up on the level in the tank. I had NO other symptoms, the truck ran great, no oil in the water, no water in the oil, no steam from the TP ...

Do a compression check... and if the radiator is more than 5 years old, have it flow tested... or replace it.

When you have the head off definitely replace the timing belt, and also the water pump. If you've got extra cash laying about it would also be a good time to replace the oil pump, but most guys will tell you they rarely go bad. (probably true). Same with the front crankshaft seal, it's a pretty easy replace, and as Rufus says, "cheap insurance" .

Good luck!
JB

Hmmmm, three days ago, same exact post over on 4x4 wire... pics were offered... never replied ... oh well.

Wasn't me.....I hope. I do what Isay I'll do .....unless I absolutely forget. :(

No! not you... the original poster, JALinker... yer cool...

C/YA!
JB

so, is here the better place to discuss things or over at 4x4 wire?

Don't think it much matters, lots of guys read them both, I think the "wire" has a bit more activity, and this board is geared more toward hard-core "fabbers", where the wire is more "daily driver" and "tamer" rigs. But ya get a mix of both on both, so it's yer choice.

C/YA!
Jeff

Concerning the fuel pump issue......I recall my 90 trooper's fuel pump's relay gets its on signal from the ECM. Goes something like this: At initial ignition switch turn on, the fuel pump relay gets a few seconds of on signal from the ECM to prime things up. Then, the ECM only provides on signal to the fuel pump relay if it detects activity from the ignition(no matter if during cranking or actual running). I imagine this is a safety feature. My 90 trooper also has a loose wire in the wire harness that leads to the fuse/relay box under the hood. The purpose of this wire is to bypass everything that controls the fuelpump and force the fuel pump on. I can't remember how this wire is used. :shaking: It's plugged into something and that makes the fuel pump run. I believe it's the 12v side of the circuit that powers the fuel pump. If you jumper 12v to that wire, you are directly powering the fuel pump.
So, if you know for sure the ECM primes the fuel system at initial ignition turn on, and if the engine only stays running when you jumper power directly to the fuel pump, then here's what you know: The ECM has control of the pump(priming activity), and the ecm is probably not running the pump, because it's not getting ignition activity signals (ignition or wiring fault), or the ECM is getting ignition activity signal but is failing to detect them (ECM failure).
Anyhoo, I hope your 88 is similar to this. With access to the ECM, you can probe the ECM connector terminals with a volt meter and test for the fuel pump on signal coming out, and the ignition activity signal going in. Good luck!

I will check this out! Thanks, Rude Dog

Here's how it goes in my '88 :

You turn the key to START, the starter relay energizes.

When the starter relay energizes, it also turns on the fuel pump through the normally open contact of the fuel pump relay _as long as you have the starter operating_ .

Once there is output from the ALTERNATOR, the ENGINE RELAY is energized. The ENGINE RELAY then in turn energizes the FUEL PUMP RELAY .

FUSE 24 being blown will cause a Start, then die symptom, as will a bad fuel pump relay. I think the Engine relay can also cause this, but you would probably have other symptoms along with it.

I'm pretty sure FUSE 12 will also cause the Start/Die ...

The oil pressure switch also comes into play here, but I can't quite remember exactly how. I'm not sure, but I think if there is no oil pressure, the fuel pump shuts off. A safety feature for sure!

Pulling the fuel pump relay and jumpering pin ?3? to pin ?5? (CHECK THIS IN A MANUAL BEFORE YOU DO IT! IT MIGHT BE PINS 1 AND PIN 3 , NOT SURE!) will turn the fuel pump on ALL THE TIME, even with the key OFF ! Good for fuel pressure diagnostics!

JB