I am helping my son with his 87 Iroc. He drove it the other day, all was normal then wouldn't stay started. We changed the fuel filter, checked the lines, pressure is ok, as far as I can tell the fuel pressure regulator is good. The diaphram isn't leaking anway. No codes show up either. The trouble chart says something about removing or disconnecting the distributor by-pass lead ?? What's/where this?
Disconnected ECM no help, No moister under cap ( my first thought ), injector fuses good
TPI, 305, Standard coil not HEI
Thanks for the help, I am trying to get it running so I can have my car back.

 

sounds like vats but I am not sure a 87 had vats or not

how are you checking the fuel preasure?

so you have a noid light to check the injectors

you could take out your ignition module and take it somewhere to get tested

oh by the way if you have vats you will have a chip in your key.

good idea at the time but now that the system is old it tends to have issues

 

No VATS

We didn't have a gauge will get one today but got a lot of flo out open line and couldn't hold back the pressure with my thumb. I know it's not accurate test but still lots of pressure. It fires like once or twice and that's it don't truely "start"
He checked the fuses under the dask, I assume these are all the fuese? Or is there another location for the injector fuses. They show 2 in the book. But not where they are at. Only found 1 in the fuse panel

 

Thanks for the inputs I recieve here. I am knew to this forum. I have been reading other threads to see if I can pick up anything. I noticed someone asking to close the threads when we are done. Sorry I don't know how and not all that great on computors anyway. Took me awhile to get this far. So when I am done I will close with a very grateful thanks but please tell me how.

 

Check for spark when it won't start. Easy enough to do and won't require any special tools. Just pull a lead off one of the plugs and hold it (with insulated pliers) a short distance away from a ground. Have someone hit the starter and you should see the spark jump the gap. You may need to put a screwdriver or other conductor into the boot to do this.

If the spark is good, go on to check air and fuel.

To close out a thread, just post back when and how it was resolved. Let's us know it turned out alright and may help someone later when searching with a similar problem.

 

Thanks, I am assuming and I know that ain't good but before I showed up on the scene they shot starter fluid in the intake and it ran on that so I assume good spark.

 

Wouldn't hurt to duplicate that test again, especially immediately after a no-start condition. That would rule out air and spark and you could concentrate on fuel. Go on to test pressure and injectors.

A common failure is the ignition module. It will start when cold, run fine all day then refuse to re-start while it's hot. A few hours to cool down and it will work fine. Why it's important to check spark while it's refusing to start before moving on.

 

Ok will do more testing.

This is a TPI intake FYI

 

Yeah, 8 (or 9) injectors. Fuel pressure requirements are much higher than TBI and more likely to cause problems.

 

9 injectors

 

What PSI should I get?

 

42 psi or higher,jimmy

 

Been replying too fast and some of my earlier posts were double merged. Make sure you didn't miss anything.

Again, most likely IMO is fuel but spark is too simple to rule out.

 

It does sound like your pump is not able to keep the pressure it needs. Either the pump strainer is clogged or the pick up line is cracked.