Delta 88 does not start when hot!

[CrazyDemon]

Hi everyone!
I have an odd problem with my 1989 Delta 88. When I try to start it in the morning, or after it's been sitting for a long time, she starts no problem; every time. However, after I shut the car off and let it sit for a little while (30 mins to 3 hours), it refuses to start back up. Sometimes it starts, but runs very poorly and always dies unless I give it some gas. If I floor it, it runs extremely rich, (I think) with clouds of black smoke coming out of the back.

Leave it for another 4-5 hours to cool down, and it starts and runs perfectly!
The fuel pressure is normal. Around 40 psi before starting, and 30 psi while running. This doesn't change from hot to cold. Spark is also strong when running, and it sparks when trying to start and not starting.

Any ideas would be appreciated!
Jack.

[maxwedge]

When this occurs disconnect the maf and see what happens.

[dhspring]

I think you might have a bad fuel pressure regulator. Put your gauge on and check the fuel pressure, it should hold some amount of pressure for at least 3 or 4 minutes after you turn off the ignition. Check the book for that static pressure number, I'd guess at least 40 psi, if it bleeds to zero quickly, you have a bad regulator. Now the good news, if it is the regulator, it's quick and cheap to replace, it's right there on the fuel rail and will cost about $50 at a parts store, good luck.

[CrazyDemon]

Originally Posted by maxwedge

When this occurs disconnect the maf and see what happens.

You are right. It was definitely the MAF sensor. Got a new one and all of a sudden she runs like a dream. However, It's been a few months since we replaced the MAF sensor, and it died... So we got a replacement under warranty from Parts Source and that one was again good for a few months and they also stopped working. Now we got one from a local pick-your-part and it seems to be working fine again, but I'm afraid there may be an underlying problem causing these to go bad...

Do you have any ideas?

[maxwedge]

Typicallythe reman units have been problematic, escpecaially Cardone units. This is too old to continue, so start a new thread if so desired.