What would make my car do this? - Second Generation Forum

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What would make my car do this?
Tuesday, May 31, 2005 2:07 PM
I've had this problem for a while now but havent really tried to hard to fix it cause the car isnt on teh road yet, but since I'm putting it on the road soon I pretty much have to fix it, the problem is it dosent run, lol
When I first got the car the motor was done, so I put a new one in and it never ran more than two seconds since then. I'm not getting fuel for some reason, The fuel pump is fine the fuse is fine the relay is fine, if I apply 12 volts to teh test connecter it pumps fuel but the injector dosent inject it, then I by passed the relay just connecting the two fuel pump wires together so now the pump comes on with the key, but I just cant get the injector to inject fuel, I know the injector is good cause I have a fuel injector tester kit that has a plug that applies power directly to the injector and it works so I have some kind of wiring problem.
Basically my question is does anyone know what would make your car cut fuel?
any help greatly apreciated, thanks in advance





Re: What would make my car do this?
Tuesday, May 31, 2005 2:08 PM
O yeah, I guess it would be nice to know what I have, lol
Its a 89 sunbird 2.0 OHC auto.




Re: What would make my car do this?
Tuesday, May 31, 2005 4:21 PM
Is it MPFI or TBI? I had a TB 2.0 OHC that had the opposite problem, whenever I turned on the switch the injector sprayed full blast and immediately flooded the engine. I had an extra computer laying around so i put that in and it solved the problem.


<img src="http://www.geocities.com/fudd_22602/elmer-shoot.gif"> Old school Js rock
Re: What would make my car do this?
Tuesday, May 31, 2005 4:35 PM
Are you getting spark. of course you might have the distributed motor.
If you arent getting spark and no injector pulses, its either the cam sensor or ECU itself.
could always be a bad wire somewhere as well.



Re: What would make my car do this?
Tuesday, May 31, 2005 5:30 PM
Its a 89 so its TBI and has a distributor, and I know I'm getting spark, cause after I use the tester that makes the injectoer work for a few seconds it sprays some fuel into the TB and when I crank it over it will run for a few seconds, then die. So if I pour gas down the TB it runs, I think its a wiring thing, I'm going to try swaping ECM's I have a spare but its for a standard car, it was in a auto car when I found it and the car ran but I want an auto ECM to make sure, cause I know standard cars dont start unless the clutch is down, and not having a clutch in my car I can see the ECM starting it which it dosent, but I think the problem is else were.
I bet its just a broken wire though, anymore theory's
thanks for the help so far, I would have never thought to check for cam sensor, Cause that might stop fuel, I was checking all the sensors on the TB and they were all fine.




Re: What would make my car do this?
Tuesday, May 31, 2005 7:36 PM
i figured it out.

it's sad that it's a 2.0 OHC and not a 2.0 OHC turbo it just wants to be boosted, that's all



...

Re: What would make my car do this?
Tuesday, May 31, 2005 8:39 PM
muahahahahaaaaa....





so true.



Originality and Creativity surpasses Popularity

Re: What would make my car do this?
Wednesday, June 01, 2005 10:27 AM
Tyrin...

Spinning dizzy shaft creates AC signal through pole piece/ pickup coil. Module uses signal to 1) create spark at coil, (2) create REFerence signal for ecm. ECM uses digital REF signal to decide (1) crank is turning, (2) how fast crank is turning. ECM then energizes injectors based on internal tables for specific rpm, coolant temperature, map, etc. If RPM exceeds limit in calibration, ecm sends 5V signal back to module so module uses ecm generated timing values.

If ignition module tester generates ignition pulses for ECM, and ECM triggers injectors, then all is wlrking correctly. If the tester is replaced with module, and no injector pulses, then something in distributor is faulty. If module delivers spark but injectors still no worky, then pickup coil and pole piece are working correctly.

Modules can be funny. There's a low tech test that involves connecting one end of a test light to battery + and touching the other end to the + connection at the pickup coil. With the key on, the coil should produce spark. If the ecm is connected, the injector will also fire. I've seen a module work correctly for this test, then correctly for a few seconds to a few days after trying this test. I've also seen modules that produce spark but no REFerence pulses, and modules that work until they are warm. If you have a spare distributor, you might try plugging it into the car and spinning by hand.

hth

-->Slow
Re: What would make my car do this?
Wednesday, June 01, 2005 2:30 PM
im tellin ya, thats not it... it wants boost

boost is what makes every motor happy. and the motorist even happier


...

Re: What would make my car do this?
Wednesday, June 01, 2005 2:38 PM
Yeah I'm sad its not turbo as well, lol But I'm waiting until I finnish all my exterior and interior stuff first cause I'm still collecting parts for the motor and suspension. Once I have all the parts I want to turbo it I'm going to pull the car off the road for a few days and turbo it, but right now I just want to get it on the road.
Thanks slowolej, That helped a lot, I was suspecting something with the distributor but wasnt sure, now that I know thats were the ECM gets the signal from I can look into it. I have a feeling the answer to my problem is in your post but I got lost in some parts, lol it was kind of confusing. So is it something in the distributor or is something in the conector on the coil. And what do you mean by "pickup coil" You've got some terminology in there I've never heard (thats what I hate about the internet everyone has there own word for everything)
thanks




Re: What would make my car do this?
Wednesday, June 01, 2005 6:19 PM
I was gonna guess gremlins...but I guess that's just me.


-----------------------
1997 Cavalier Z24
1992 Cavalier Z24 - *RIP*
"I consistently feel like something's missing out of the new cavvy. I'm pretty sure its 2 cylinders."

Re: What would make my car do this?
Wednesday, June 01, 2005 8:34 PM
Ya know, Sunvalier, I'm gonna use that at the shop the next time one of the school buses won't start. I just can't wait to build a twin turbo bus.

Tyrin, sorry for the confusion. I'd tried several times to type a reply but just couldn't get the time. I finally blasted out that answer when I had a few extra minutes.

"Pickup coil" is GM's term, not mine. GM has used the same basic ignition system since about 1975 (actually, big block 'Vettes in 68 and 69 with (3) 2bbl carbs also had a similar system).

If you look at this picture, you'll see a green wire and a white wire. On the RH side of the distributor the wires are connected to a black ignition module. The module has an Accell sticker on it, which is worth -5 points in my book. At the other end of the wires is the pickup coil. Part of it is hidden, but if you look you can see 2 gold colored screws (one on right, one on left, the third is hidden) which are part of the pickup coil. You would have to remove the distributor shaft to clearly view or remove the pickup coil.

If you look carefully at the pickup coil you'll see little "teeth" or "points" which face the center of the distributor. The pole piece, on the distributor shaft, is also somewhat visible in that picture and has teeth which face the pickup coil. The arrangement looks something like this:



^
< > Pole Piece
v

_ _
/ v \
/ \
|> <| Pickup Coil
\ /
\ _^_ /

_ _
/ v \
/ ^ \
|> < > <| Pickup Coil and Pole Piece
\ v /
\ _^_ /
As the magnetized pole piece spins it causes an A/C signal to be generated in the pickup coil, which is (obviously) connected to the module. That signal gets converted to an ignition pulse and a reference signal for the ecm.

Look for articles about how HEI ignition works, especially articles talking about HEI on EFI vehicles. If you have a factory service manual, look in section 8D for more information on the ignition system.

hth
-->Slow
Re: What would make my car do this?
Thursday, June 02, 2005 4:06 AM
Yikes! Look in section 6D, not 8D, for engine electrical information.

-->Slow
Re: What would make my car do this?
Thursday, June 02, 2005 12:55 PM
Thanks again slow, thats exactly what I was looking for I'll look into that tonight, hopefully that my problem, I dont have any spare distributors right now so I'll grab a few hwen I go to the wreckers next to test it and see if thats the problem, when I put the new motor in it didnt have a distributor on it and I had to use the one off my old motor, then when changing the motor I smashed the distributor cap and had to buy a new one so I always suspected something wrong with teh distributor, but then when I was getting spark I stopped worrying about it cause I wasnt sure were the ECM got teh signal from.




Re: What would make my car do this?
Thursday, June 02, 2005 9:25 PM
Yeah its the ignition module for sure, thanks guys




Re: What would make my car do this?
Thursday, June 02, 2005 10:03 PM
i didnt read all this because its long and im lazy. but i had a problem once where the car would run for 2 seconds and die. it was the wrong module. one module will not send a signal back to the computer after it starts, and when the computer doesnt get the signal, it kills the car. i bought a new distributer and it had the wrong module...switched the module, started right up.


WARNING: I bring nothing to the table.

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