90 Lumina 3.1 dies at acceleration

[dtaylor2]

My car is a 1990 Lumina 3.1. I have already found it to have a bad fan relay, but there's another problem that I'm having trouble identifying. I start it up cold, and it will idle. Then, when I push the throttle, it quits. Sometimes, it'll start and run fine. I have no check engine light, even when it's acting funny. It has new plugs and wires. The more times I start it and it dies within a few hours, the shorter the time it'll idle before it dies on it's own. I think an ECU sensor somewhere is going bad. Does anyone know what one it might be?

[richtazz]

First thing you need to check is fuel pressure. If the pressure is low, it will idle, but as soon as you hit the throttle, it will die.

[dtaylor2]

Cool. I'll check my fuel pressure and post again when I get it checked. Thanx.

[dtaylor2]

I couldn't check the fuel pressure, but I've got more info. If any1 can help, that would be awesome. OK, in addition to what I've listed above, it will actually start out running and revving, but as it gets increasingly warmer,the problem persists until it won't start at all(not due to overheat). It is not the fuel filter. We got a check engine light 4 the first time 2day. At first it was only once when we revved it, but as we let it run, it eventually happened at idle too. We put in the code key, and it blinked once then stayed on. In fact, it did that several times w/o the code key in too, but only after we got the check engine light while it was running. Also, I thought it was running rough because we put in a new battery, but the idle hasn't gotten any better since we got it a month ago. If any1 could tell me anything about what my engine code means, that would be awesome!

[maxwedge]

Those numbers don't correspond to a code. after 12, then you would have numbers blink in sequence like 3 flashes then 3 flashes, 33. Again the fuel pressure should be checked here, you cannot skip this process.

[dtaylor2]

I don't have the thing to check the fuel pressure with, and my dad wants to find out what code the engine light was and as it turns out, it wasn't a code key, we just crossed the 2 terminals. We didn't even get 12, so that means we weren't in diagnostic mode...sorry 2 be annoying about this, LOL. umm...I'll get the code readout and fuel pressure (if at all possible), and get back with U guys.

[richtazz]

To pull the codes, the key has to be in the "on" position without the engine running. You jump terminals a-b of the ALDL, and count the flashes. Just wanted to clarify in case you were jumping the wrong 2 terminals, trying it without the key on, or with the key on and engine running. Here's a link to the general proceedure, as well as a partial list of code definitions (it references 3rd gen f-bodies, but it applies to your car too).

http://www.sethirdgen.org/dtc.htm

[dtaylor2]

We checked the fuel pressure. It was 42-44 psi. We got the code, it is:

12
33
35

We replaced the map sensor, and it still didn't fix the problem.

Hi, this is Dtaylors dad. One time we started it it ran fine, as the engine got warmer it started cutting out when you accelerated it. This got worse until it would only idle then die. Other times you start it it will not accelerate at all. Some times, like yesterday, it surged and idled at about 1500 rpms. It idels very rough. It had the plugs and wires changed as well as the fuel filter and air filter. Today all it will do is idel and die. There is vacume to the map sensor. Any suggestions would be greatly appreciated.

[dtaylor2]

My dad and I just figured out the general problem. Although the ECU codes were MAP and MAF sensors, we changed both, and it didn't help. My dad said it could be the crank position sensor. SUre enough, there is a CPS behind a harmonic balancer and the harmonic balancer didn't look like it was setting right, and we checked it, and it isn't. We have yet 2 figure out why it isn't set right, as we found these things out at 8:30 last night and it was cold. I just thought I would keep U guys updated!

[richtazz]

GM didn't use the crank sensor behind the balancer on a 3.1 until 93-94. If your 90 has one behind the balancer, the engine is from a different year car. Your car should only have the crank sensor in the back of the block.