'89 not starting... ignition module??

sorry for the re-post but I can't find the post I read that is relating to my topic of choice ( well not really my choice ). Car sat for a couple months, ran completely fine. Went to start it today turns over fine but not getting any spark. I can hear the pump, I poured a little gas down the carb and still nothing, not even back fire. Now I've been told that these little bastards don't have distributors but ignition modules what the hell are they. I read a post on how to replace them but that was for a 91 6 cylinder. Are they roughly the same, behind the exh. man. shield, remove couple motex wires or something and then the three bolts holding it in?? Any suggestions woudl be much appreciated.

thanks.

I would check the crank posositon sensor first. Its like $15 to replace. It tells the ICM when to spark. If it goes bad it wont tell the ICM anything so you dont get any spark. try that first, and while your at the auto parts store getting the CPS, take in the coil packs and ignition module and have them tested as well. Three screws and the whole assembly comes off. They're on the front of the engine under the exhaust manifold.

thanks for the reply, I've replaced the Ignition Module with a new one (easier than getting it tested haha not really, piece of mind) and the car turns over but still not firing, tested each spark plug by taking out and holding against cover, all spark fine. Pour gas down the carb it almost started and then died again. Now I was thinking the CPS, but if I'm getting spark to my plugs that wouldn't be the problem, or is that the timing of it? My question is the module/coils. How do you reconnect the cylinders to the pack. the book says 1,3,4,2 so that means cyl 1 - 1, cyl 3 - 2 and so on, right? But then the book also says that each cylinder should be connected to its respective number on the module ie 1-1 2-2 etc.?? If you have any suggestions or to resuggest the CPS let me know cuz I've boggled three mechanics so far with this one!

thanks

If you are getting spark, the CPS, coils packs, and ICM can be ruled out.
Sounds to me like no feul pressure. Confirm that the pump works, and get a feul pressure tester to check pressure at the feul rail. That kinda sounds like a ruptured FPR.
1,3,4,2, is just the firing order of the cylinders. The coil pack connections go from left to right 4,1,3,2.

kooterskkar, according to the parts stores where I live there is no such thing as a fuel pressure regulator for this car. Now this could be stupid question but are they fuel pump pressure switch and the fuel pressure regulator the same thing?? This coming from what's listing in their parts books and don't show a FPR?? Let me know as I've looked the part up on the net and found it but apparently up here in Canada we don't sell the FPR.

thx

also, how much do FPtesters run you down there, up here the dude said for TBI FPtester would be AT LEAST a couple hundred dollars!1!??? Well supposedly one of the biggest autoparts stores don't know that there are FPR's cuz I found one at the smaller autoparts store for 40bux, but its the Fuel Pressure Regulator Diaphram/Kit is that the same thing as what I'm looking for? (as you can tell I'm not a full time mechanic)

thx bro.

If its feul injected its got a an FPR. Feul injection doesnt work without a regulator to control how much feul the injector spits out at a time.
Is that engine TBI or port injected?
Autozone has a halfway decent FP tester for $35. If yu dont have one yu can also look at Advance, Pepboys, Napa, or any other parts stores you have around there (except for the one that told you they'd cost hundreds, of course) Just look in the tools section.

kooterskkar, is this so called FPR just like a little gasket looking piece? Cuz that's all that came in this box that I ordered. I know what I fuel pressure regulator looks like but this thing is absolutely not even close to what I know one looks like. So far I've changed my ICM and fuel filter, can hear the whirr of the pump, plugs are sparking. So am I only left with this regulator? And to top it off I don't see a fuel rail, it usually sits about the intake manifold on most cars right!? well this thing doesn't have one. And to answer your question its "suppose" to be TBI

thx bro

sorry for the re-post but I can't find the post I read that is relating to my topic of choice ( well not really my choice ). Car sat for a couple months, ran completely fine. Went to start it today turns over fine but not getting any spark. I can hear the pump, I poured a little gas down the carb and still nothing, not even back fire. Now I've been told that these little bastards don't have distributors but ignition modules what the hell are they. I read a post on how to replace them but that was for a 91 6 cylinder. Are they roughly the same, behind the exh. man. shield, remove couple motex wires or something and then the three bolts holding it in?? Any suggestions woudl be much appreciated.

thanks.


The ignition module is under the distributor behind the air filter. Mine used to come and go. I tracked it down to the moduile and bought a new one and now it works fine.
1991 GMC 4x4 305 tbi. 198000 km and climbing

If its TBI, your gonna have one central feul injector. It works just like a carburetor but it uses a feul injector instead of needles. The best I can do for help is to just point you in the general direction of where to look. Follow your air intake hose to the throttle body, take it off and take the top off of the throttle body. Look straight down into it, right in the middle is the feul injector. I really cant say where the FPR unit is, I havent worked on any of the TBI models.
I think you may end up having to get a mechanic to test the feul pressure for you. Thats about all the help I can offer for this problem. I suppose it could be a bad feul injector. I dont know how to test those though.

alright, I think I might have to break down and take it to a mechanic. Thanks for the help though.

which engine does your car have, from what I gather it's a 4-cylinder, but clarify it for me

the pressure regulator is on the throttle body of the 2.0 4-cylinder on the top of the unit under a round cover secured by two screws. It isn't replaceable as a unit, but is rebuilt using a kit that includes the diaphragm and spring, plus the seals.