3.1L to 3.4L luminas from 90 to 93 no start problem

[93z34]

Ok, I recently bought a 93 lumina z34 as is with the infamous no start problem. I have been reading these threads for about a week now and refering back to it when trying to fix the car. From what I can tell I have the same problem as every one else.

As with every one else, I've replaced the CPS to start with and that did not fix it. It is getting spark and the fuel pressure is good. From the way it sounds when im cranking it or it runs for the few seconds then dies, the timing is way off. Plug wires are good and its got new plugs that are gapped to .045. I pulled the timing belt cover off and the belt is frayed and cracked in a few spots... I know, it needs changed, but that would not keep it from starting.

So far every one I read about on here say's the problem starts by it stalling or sputtering when the engine gets warm. Then now start untill its cool again, eventually turning into what i got going on.

Every one so far has changed the ignition module and coils, fuel pump and filter, plugs and wires, injectors and rail, EGR, crankshaft sensor, oil pressure sensor, and the dredded ECM. And after all that, they still have the same problem.

From what I can tell every one on here has been a great help to narrow down all these items but with no avail. No one has posted yet that they have discovered what the issue is and that thier car is fixed. Most of the time they get down to replacing the ECM and then nothing is posted after the fact that it didnt fix it.

Please help!! For the sake of all of us. lol

Thank you

[93z34]

So, I just went out and tried to start it again and same thing, starts and runs (out of time) for a few seconds and cuts off. Then wont fire. cranks but no fire.

It has got to be electrical. Some thing is telling the engine to quit and telling it not to fire until it has "re-set" or something. I just know that when I get a response some one will tell me ICM. Thats not IT. lol. I just wish some one on here has had this problem and fixed it for good and can tell me what they did before I dump more cash in this thing that I dont have to start with.

[maxwedge]

Try firmly tapping the pcm, see if it changes anything, this was a common issue.

[93z34]

thank you max. that is the one thing i think i havent tried yet. i will try it this afternoon.

[ChrisinVT]

When my car started doing that shit I parked, and eventually stripped/junked it.

[93z34]

i see why you junked it. lol. there isnt a fix for this.

[ChrisinVT]

Yeah, I found it easier to just buy another Lumina and use that one for parts.

[Lukewarm256]

i havnt had the no-start problem, exactly... i have a flooding @ start problem, because .. well, i'm not EXACTLY sure, but it's probably 90% chance that atleast one injector is stuck open.

SO, yours could be that as well--it may start, but with that injector open, it floods, and it wont start anymore. try putting the pedal to the floor to got it cleared.

OR, the timing belt you mentioned is going bad, and has slipped. perhaps there is a timing belt tensioner (i dontknow if there is on this model) that's gone bad, and it's letting it move, or has moved. that would make you think that it's out of time... ya know?

OR, maybe the catalitic converter is plugged. aparently stuck injectors arnt radically uncommon for these cars, so this is possible, and would keep the car from running even if these are fixed. SO, to test this, unbolt the exaust system @ the headers (can take off front upper motor mounts,pull motor forward with ropes to get to bolts better). if it starts and runs with the pipe off, you'll know it's the cat (may run like crap, because there's a second 02 sensor after the cat).

if it were me, and had done everything else, i'd check that cat--after back pressure builds, it just cant run.

above all, good luck!