That's what I'd do too. Then it still probably wouldn't work. Is there anyone close by that can help him out? 7 years has to be some kind of record! Poor guy, this sucks.
Anyone in travel distance to Grand Rapids MI? There may be a steak diner or compensation of your choice in your future. Thanks, -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
Paul, if you can turn on the ignition and hear the fuel pump relay click, then you hit the starter and it will momentarily start, then the fuel pump isn't dead. That 1.8 second pressurization cycle is getting fuel up to the engine. It needs the fuel pump to do that. During that 1.8 second period, the ECM doesn't need to see a spark signal to make the fuel pump run. Once the engine starts to turn, the ECM must see a spark signal to turn on the fuel pump circuit again. If there's none from the ICM or pickup coil, it won't start. Obviously you're getting that spark signal or it wouldn't fire off for the first brief moment. Again, it needs to be confirmed that the engine will continue to run while something is being sprayed into the intake. If it won't then you should look toward the ignition switch and starter circuit.
The illustrated ballast resister is irrelevant to the Fiero. The Fiero distributor cap doesn't use that ballast type contact to the rotor button. They use a graphite button.
You got it. The fuel pump is dead, the distributor is questionable, and who knows what else. Where exactly is that heating ballast resistor that mice like to nest in?
in the heater box, near the HVAC fan under the front hood.
Originally posted by fierofool: The illustrated ballast resister is irrelevant to the Fiero. The Fiero distributor cap doesn't use that ballast type contact to the rotor button. They use a graphite button.
the illustrated part is completely different and unrelated to a ballast resistor, it's a rotor button, large cap HEI's use a spring loaded rotor button, small cap HEI's use a sprung rotor.
Paul, if you can turn on the ignition and hear the fuel pump relay click, then you hit the starter and it will momentarily start, then the fuel pump isn't dead.
I hope I haven't confused everyone to badly. It was 7 years ago that the car had the start and die problem. Things ground to a halt then and I more or less spent the next 7 years searching for a nonexistent ballast resistor. The original problem was never tracked down, and now there is a list of new problems caused by long term storage. One of those problems is the fuel pump that doesn't make a peep. Not even a groan when I force feed it 24V through the ALDL.
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. Once the engine starts to turn, the ECM must see a spark signal to turn on the fuel pump circuit again. If there's none from the ICM or pickup coil, it won't start. Obviously you're getting that spark signal or it wouldn't fire off for the first brief moment. Again, it needs to be confirmed that the engine will continue to run while something is being sprayed into the intake. If it won't then you should look toward the ignition switch and starter circuit.
That is pretty much the plan, but I am going to thoroughly debug and then clean the the distributor first. -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
The pink wire(s) at the coil should have 12 volts cranking or with the key in the RUN position.
Try what Fierofool said - spray a little starting fluid into the throttle body & see if it runs longer/keeps running.
You may not have an ignition problem, the injectors may not be working. The cold start injector will spray gas while cranking, when the key returns to RUN it stops - just enough fuel to try to run. The distributor and cold start injector will work even if the ECM does not.
Does the orange CHECK ENGINE / SERVICE ENGINE SOON light come on in the RUN position? The ECM may not be working (no injectors) if it does not come on. Check the 2 injector fuses under the dash also.
There is only one set of contacts and it also powers the ignition and the gauges.
So if your tach & gas gauge drops dead as soon as you release the key from start to run AND your check engine light is also out, suspect the switch. If your tach and other gauges stay on, and the check engine light comes on then it is not the switch.
I have a 88 that did this after replacing the IGN switch. Turns out there is a small amount of adjustment. As soon as I would release the key it would go to the run position and die. I would listen to phonedawgs.
You may not have an ignition problem, the injectors may not be working. The cold start injector will spray gas while cranking, when the key returns to RUN it stops - just enough fuel to try to run.
I saw that when I was following the START circuit. It caught my attention because it would stop the fuel flow instantly the instant the key went off start, just like my engine dies the instant the key goes off start. That would require both banks to have gone out at once. The 2 are so independent, their only common failure point would be inside the ECM. But how could the car be starting if the ECM was dead? I was about to ask on the forum if just the FI part of ECM could fail when I saw on the internet:
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Originally posted by AL68: The distributor and cold start injector will work even if the ECM does not.
Aha!! That would explain the symptoms PERFECTLY!
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Does the orange CHECK ENGINE / SERVICE ENGINE SOON light come on in the RUN position? The ECM may not be working (no injectors) if it does not come on.
Unfortunately, it does come on. Damn, I thought we had it. Could it still be an ECM problem? I am going to jumper the ALDL tomorrow and see if I can get a useful error code.
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Check the 2 injector fuses under the dash also.
Both look like new.
I think we are getting close. Thanks, -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
I would take the snorkel off and make sure the engine stays running on ether.
Just have someone else start it and then feed it ether, not too much and confirm it stays running.
IF
IF it does - then the thing is to check to see if the ECM is sending the injectors pulses. Back probe the injector wires at the 6 pin weatherpack flat connector (2x3 for 88s) where the injector sub harness plugs into the main harness. Do this test with the harness plugged in. Slip the backproble up until it touches. Then using a powered data test light see if you can see the ECM fire the injectors.
Originally posted by phonedawgz: ....check to see if the ECM is sending the injectors pulses. Back probe the injector wires at the 6 pin weatherpack flat connector (2x3 for 88s) where the injector sub harness plugs into the main harness. Do this test with the harness plugged in. Slip the backproble up until it touches. Then using a powered data test light see if you can see the ECM fire the injectors.
A direct test of the #1 suspect on my list, I LIKE it!
+1 on the starting fluid to see if it stays running - need to know to see what to test next.
one idea - unplug the throttle position sensor & see if it will start. if it's stuck/shorted above 2.5 volts it will put the ECM in the clear flood mode disabling the injectors. test for codes first - this may set a code 21 for the tps
I have a 88 that did this after replacing the IGN switch. Turns out there is a small amount of adjustment. As soon as I would release the key it would go to the run position and die. I would listen to phonedawgs.
My manual shows how to replace the switch, but says nothing about adjusting it. Can you give me some details on how to do that, or a link? Thanks, -Paul
Originally posted by Paul.S: I am going to jumper the ALDL tomorrow and see if I can get a useful error code.
I got Code 12 only, the one that should be there every time you test for codes.
Code 12 - No Reference Pulses to ECM This code will flash whenever the diagnostic terminal is grounded with the ignition in run, and the engine off. If this code appears while the engine is running, no reference pulses from the distributor are reaching the ECM
The Trouble Codes come from the ECM, don't they? Could the ECM still be bad if it is generating Code 12 and no others? -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
The ECM could function digitally but the output drivers that drive the injectors could be bad. Unlikely since there are two of them but a possibility. The Harbor Freight light will tell you if you have an output on the injector wires.
One more test you will want to try btw, and this one is free. Turn the key on and let the fuel pump run for two seconds. Then it should turn off. Then with the shortest possibility of cranking just bump the starter. Do not crank it because you don't want the oil pressure to build up and throw you off. Just a minimal bump. The fuel pump should come on for two seconds and then turn off. If the ECM runs the fuel pump for the first two second run it indicates the ECM is running and the fuel pump relay is good. If the slightest bump runs it again, then you know the ignition pulses are reaching the input of the ECM. The ECM uses the ignition pulses to know the engine is turning over. No ignition pulses to the ECM, or if the ECM fails to recognize them, then the ECM won't fire the injectors.
The ECM turns on the fuel pump relay when it sees ignition pulses and keeps it on for two seconds after
Cranking the engine can build up oil pressure and THAT also will turn on the fuel pump. You will know if it is oil pressure by the fuel pump running for a much longer time than two minutes. If you are unsure if the oil pressure switch or the fuel pump relay is which is turning on the fuel pump just unplug the oil pressure sender connector. Then only ECM controlled fuel pump relay can turn it on.
Btw, there is nothing that disables the fuel pump at the loss of oil pressure. The only thing the oil pressure sender/switch does is 1 - run the oil pressure gauge - and - 2 it can also provide power to the fuel pump, just like the relay does.
To check the ignition switch I tested the pink wire on the coil, right rear. No power in the off position, power in the on position. This rules out any problem with with the switch, doesn't it?
I tested for spark with a Harbor Freight tester, the whole thing would light up red at a regular pace, ignition seemed ok.
I backprobed a pink wire connected to an injector with the HF logic probe. With the key in the off position it tested steady ground, as I expected, and the same in in the on position (see below). In the start position it was steady red. This puzzles me. If the injectors were not getting a signal, I would expect green. If they were getting a signal I would expect pulses, red no more than 25% of the time (no longer expect it to be exactly like this). What does steady red mean? Thanks, -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
[This message has been edited by Paul.S (edited 11-30-2014).]
The switch should be ok if power at the coil. Did you try starting it with the throttle position sensor unplugged? The ECM will shut off the injector drivers if it's stuck high. Will it run on starting fluid?
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With the key in the off position it tested steady ground, as I expected, and the same in in the on position. In the start position it was steady red
This may be a problem - double check for no power at the injector (pink wires) with the key on, there must be power for car to run. Power cranking but not in RUN shouldn't be possible - the power source for both key positions is the same. Do you have a regular test light? The HF light may be giving you a wrong reading.
The pink injector wires should have a red light (12v) in the START position but it should also be red in the RUN position (12v), green/ground in OFF. If no power check for power on both sides of the 2 injector fuses. Pull them out & check for corrosion also. If the fuses have power and no power at the injectors you have a wire/connection problem.
You need to test the other injector wire (blue or green) for pulsing. should be red / 12v with the key on & probably blink green to red cranking.
Red indicates power on the probe. Green indicates ground.
Steady red on the pink wire is what you should get with the key on. This is +12v to the injector. It is the other wire of the injector that the ECM connects to ground. The other injector wire should show red key on engine not rotating. It should show flashes of green during cranking when the ECM grounds the injector to fire it.
This may be a problem - double check for no power at the injector (pink wires) with the key on, there must be power for car to run. Power cranking but not in RUN shouldn't be possible
And it probably isn't. An error in my results was traced in part to a problem in the GF segment of my test setup (a non-driver, when I told her to stop cranking, she was turning the key to the OFF position).
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The pink injector wires should have a red light (12v) in the START position but it should also be red in the RUN position (12v), green/ground in OFF.
I retested 4 wires, the pink and pink/white power wires, and the blue/black and green/black ECM wires. They all tested the same, red in start and run, green in off. I was backprobing with all wires connected, so I was expecting each pair of power/ECM wires to test the same (they are connected through the injector coil which is, after all, just a long piece of wire).
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Do you have a regular test light? The HF light may be giving you a wrong reading.
I would like to double check with my test light, a small incandescent bulb, I believe. I should disconnect the injector wire and put the light between the ECM wire and +12v and see pulses on start? Thanks, -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
[This message has been edited by Paul.S (edited 11-30-2014).]
That means the ECM isn't firing the injectors, but it doesn't mean the ECM is bad. Are ignition pulses getting to the ECM?
The above "bump the starter and listen for the fuel pump" test should show if the ECM is receiving ignition pulses.
Also you can try probing B5, the Purple/White wire at the ECM. This should show you if ignition pulses are being sent from the distributor to the ECM. The ECM receives the pulses on the Purple/White wire. After the engine starts, the ECM tells the ICM that it want's to control the ignition timing and then sends ignition pulses on the White wire. It does this by sending a voltage on the Tan/Black wire. The Black/Red wire is only a ground.
The ECM won't send the voltage on the Tan/Black wire until the engine is rotating over 400 RPM. Thus the ICM has total control of timing until the engine starts.
[This message has been edited by phonedawgz (edited 11-30-2014).]
The above "bump the starter and listen for the fuel pump" test should show if the ECM is receiving ignition pulses.
That is a test I wish I could run. The fuel pump is dead. Stone cold dead.
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Also you can try probing B5, the Purple/White wire at the ECM. This should show you if ignition pulses are being sent from the distributor to the ECM. The ECM receives the pulses on the Purple/White wire.
Next I will backprobe the purple/white wire where it comes out of the distributor with the logic probe while every thing is connected. What color(s) should the pulses be in START mode? What color should I see in ON mode? Off mode? Thanks, -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
I'll throw this out there. Does'nt the ecu use a signal from the oil pressure sending unit to energize the fuel pump. When you first turn on the key the fuel pump pressurizes the system them shuts off. It will not start pumping again untill some oil pressure is produced.Poss bad sending unit keeping the car from running after the initial prime?
I'll throw this out there. Does'nt the ecu use a signal from the oil pressure sending unit to energize the fuel pump. When you first turn on the key the fuel pump pressurizes the system them shuts off. It will not start pumping again untill some oil pressure is produced.Poss bad sending unit keeping the car from running after the initial prime?
The oil pump switch is a redundant circuit. The fuel pump should start and run with either the relay or the oil pump (when pressure is up).
I'll throw this out there. Does'nt the ecu use a signal from the oil pressure sending unit to energize the fuel pump. When you first turn on the key the fuel pump pressurizes the system them shuts off. It will not start pumping again untill some oil pressure is produced.Poss bad sending unit keeping the car from running after the initial prime?
The fuel pump dead. As dead as a fish fossil. It draws 6 amps so it must have a good ground. Doesn't make a peep, even with +24v through the ALDL.
The main problem was there before the pump died. We have narrowed it down to no pulses at the injectors, so that area is the focus of attention now. -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
Next I will backprobe the purple/white wire where it comes out of the distributor with the logic probe while every thing is connected. What color(s) should the pulses be in START mode? What color should I see in ON mode? Off mode?
Just tested it. Steady green in OFF mode and ON mode. In START mode, rapidly blinking green. Just from eyeballing it, I'd say the green pulse lasted about 50% of a cycle.
Is this what I should be seeing or not? Thanks, -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
The fuel pump dead. As dead as a fish fossil. It draws 6 amps so it must have a good ground. Doesn't make a peep, even with +24v through the ALDL.
The main problem was there before the pump died. We have narrowed it down to no pulses at the injectors, so that area is the focus of attention now. -Paul
I have to go back and read this whole thread again. I thought you said that you have fuel pressure in the rail that goes away quickly when you turn the key too the run position. You also said that the car fires and runs for a second or two. If this is true then the pump CANT be dead. There are two independent fuses in the fuse block that run the two fuel rails but if they were blown it would not start and run for a few seconds. Sorry, I'm confused and will read the post again.
I've Read and re read this post.( maybe I'm missing something) HAVE you tried to keep it Running WITH" Starting fluid "?? easy question, yes or no ?
No.
Problem was localized to the injectors before I got to the starting fluid test. I expect that it would run with starting fluid now, but the car wont be fixed till the injectors are getting pulses, so that is what I am focusing on at the moment. -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
I have to go back and read this whole thread again. I thought you said that you have fuel pressure in the rail that goes away quickly when you turn the key too the run position.
No, never said that.
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You also said that the car fires and runs for a second or two.
That was 7 years ago, and the car was put in storage without it being fixed.
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If this is true then the pump CANT be dead.
The pump was working before, but not now. From what I read around here, it would be more surprising if it did work after 7 years of storage than if it didn't.
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There are two independent fuses in the fuse block that run the two fuel rails but if they were blown it would not start and run for a few seconds.
It might be able to start with the fuel from the cold start injector because it is powered by the start circuit, not the main injector circuits. I think that is what was happening 7 years ago, and it died when the start circuit was turned off because the main injectors never got the pulses to get them going (both fuses are good).
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Sorry, I'm confused and will read the post again.
No problem, I appreciate all the help I get. I've been confused by this for 7 years! -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
Just tested it. Steady green in OFF mode and ON mode. In START mode, rapidly blinking green. Just from eyeballing it, I'd say the green pulse lasted about 50% of a cycle.
Is this what I should be seeing or not? Thanks, -Paul
*** Corrected *** - I had first read it as you had pulses at the injectors.
Yep that is good. So you have a signal from the ICM to the ECM.
[This message has been edited by phonedawgz (edited 11-30-2014).]
Yep that is good. So you have a signal to the injectors.
The wire with the pulses is the one that goes from the ICM to the ECU, I have yet to see a pulse at the injectors. If I am seeing the signal I should from the ICM going to the ECM and no signal from the ECM to the injectors, then the problem must be the ECM or a wire/connector, or am I missing something? Thanks, -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
Of course with no fuel pressure to push the fuel through the injectors they aren't going to work so that needs to be solved. Then the next thing after getting fuel pressure will be to see if it runs. After 7 years it is likely one or more of the injectors is gummed up and the tip of the injector will need soaking in injector cleaner but cross that road if you come to it.
This all seems more likely to me than any electrical malfunction.
Of course with no fuel pressure to push the fuel through the injectors they aren't going to work so that needs to be solved. Then the next thing after getting fuel pressure will be to see if it runs. After 7 years it is likely one or more of the injectors is gummed up and the tip of the injector will need soaking in injector cleaner but cross that road if you come to it.
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Originally posted by Gall757:
This all seems more likely to me than any electrical malfunction.
Keep in mind that there are no pulses showing up at the injectors. Perfect fuel pressure and like new injectors wont help till the injectors can get a signal to open up and let some of that fuel into the manifold. -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
Keep in mind that there are no pulses showing up at the injectors. Perfect fuel pressure and like new injectors wont help till the injectors can get a signal to open up and let some of that fuel into the manifold. -Paul
You may be surprised. If the circuit is completed by the ECM grounding the injector, and the injector is stuck.....you may not see any pulses at the injector. Many cars have been stored for 5 to even 20 years and revived. In nearly every case the injectors needed to be cleaned. If you know you have a bad fuel pump and injectors, why not fix what you know and deal with what issues remain after that? (this is getting a bit Zen.....but you also may be looking for the wrong thing)
You may be surprised. If the circuit is completed by the ECM grounding the injector, and the injector is stuck.....you may not see any pulses at the injector.
When I tested the wire coming from the ECM there was no pulse there, either. -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
