AmericanThunder
Super Moderator
Read the link I sent you. Would help you narrow it down.
Sarah's 1991 Camaro
- Thread starter TransAmDan
- Start date
Havnt got that far yet, but that will be the next thing when I get a chance.
Checked the OBD code. Only getting 12's, left it going for 6 cycles. So that's good in a way.
Is that under the intake? I may be able to take the intake off and give it a tap. I could also monitor a fuel injector with an occiliscope.
July92RS
Core Member
More than possible Dan,,,Another thought is that on some the grey V+ from the pump is linked to the oil pressure switch,,if thats failed it won't send a signal when cranking
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renchero
Well-known member
Although water wouldn't directly get on the car, it could blow under the door and around the sides. Cardboard boxes disintegrated from the damp. New lifeforms have grown on the steering wheel. It's dry now, but there are rusty parts on the firewall. The floor was welded a while ago and put POR15 treatment on it, so that should still be good, I'll check the whole underbody when I can get it moving.
That link is very useful, The crank sensor info looks good and informative. I'll get my occiliscope out and take a look at the pulses.
AmericanThunder
Super Moderator
I think your looking at a component failure due to the issue occurring immediately after welding and running well before. The storage only occurred after the failure had already occurred. I have a feeling you will find the PCM at fault (did you remove the battery cables before welding?) but hope it’s more easily sourceable and replaceable components.
It has been rujnning after the welding, and battery was taken out. Good thought though.
Checked the 4 earths to the ECU and they look good.
There dosn't appear to be a crank position sensor on this engine. However looking at the pins going to the ECU there is a Distributor reference pulse, so it must use these to get a location of the crank.
Measuring across pins D8 and D9 I get a good waveform while cranking.
Checked the 4 earths to the ECU and they look good.
There dosn't appear to be a crank position sensor on this engine. However looking at the pins going to the ECU there is a Distributor reference pulse, so it must use these to get a location of the crank.
Measuring across pins D8 and D9 I get a good waveform while cranking.
Seriously, I've been there.
Fuel pump primes, then when i crank it provides power to the pump still, and then primes again after not starting,
so pump feed looking good.
next injectors.
so pump feed looking good.
next injectors.
Fuel Injector Control bank 1
Other bank
Other bank
This was measured at the ECU end. The ECU only pulls a ground, it doesn't provide power to the injectors. The injectors have a common live from a fuse. For me to see volts at the ECU it must be passing through the injector coils. so for that, the injectors should be firing. So are they blocked, or the pressure regulator on the rails. I think this is a good place to investigate. I'll need to take apart the manifold to get to the injectors. I could pop one out and give it a quick squirt into a rag.
The point the waveform was taken is points C11 and C12 (just under the two banks of 3 injectors)
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Popped in some wire so I could attached probes to monitor. Then looking through the list to check anything of interest.
It was a good session of investigation.
Squirted some carb cleaner in the intake, its about the only flammable gas that I have laying about. Then sat in the car, ignition on, you see the security light come on and then go out, this shows the VATS is happy.
AmericanThunder
Super Moderator
Do you have a workshop manual? Is the regulator before the fuel rails or on the return?
Fairly sure I have a Haynes manual covering this engine so I might have to dig it out and see what useful info might help you?
Fairly sure I have a Haynes manual covering this engine so I might have to dig it out and see what useful info might help you?
Will
Core Member
If you say there is pressure on the fuel rail, surely it should still squirt from the injectors if they are being triggered?
I get what you are saying about the ECU firing the injectors by grounding them, but I have a feeling there is 12 volts missing some where which is preventing the injectors from firing.
As has been said, I would agree that the acid test is to pull an injector and look.
I get what you are saying about the ECU firing the injectors by grounding them, but I have a feeling there is 12 volts missing some where which is preventing the injectors from firing.
As has been said, I would agree that the acid test is to pull an injector and look.
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