Hoss50

I just got back from Lake Havasu, but barely. My truck is being a POS. It dies on me after it has been running for awhile. This morning I left and made about 80 miles then it died.

I checked things out and thought the fuel pump was the problem. Changed it. It ran fine then died 30 miles later. It died 6 times but made it home. Here is the list of stuff I changed in order. Nothing fixed my problem.

(350 MAF TPI off 88 Firebird, external fuel pump, P/N grounded)

I tried disconnecting the TPS and the MAF sensor also and neither helped.

Changed:

fuel pump
ignition module
ignition coil
ECM
MAF relay (both)
fuel pump relay
EST

It is only throwing code 12.

When it dies it won't start for about 10 minutes, sometime it would start up sooner but would idle poorly and die. Then after it cooled a little while it would fire right up like nothing was wrong. Any ideas?

I thought pickup coil, but I thought when those go they are dead, end of story.

89Formula5.7

Does your vehicle have VATS? Did the ecm come from a VATS equipped vehicle? Maybe the ECM is waiting for a signal from a VATS module that isn't there.

razor

Have you looked at your reluctor closely in your distributor? I had a friend who had a distributor with a reluctor that had a few cracks in it. When it would reach operating temp, the reluctor would expand slightly, opening up the cracks causing it to stall and not run until cold agian. It doesn't cost anything to pop the dist. cap off and have a look. Also check/replace the pick up coil. The terminals on the back of it become corroded or even break causing an intermittent connection.

Hoss50

No Vats on either ECM I tried. My truck had been running flawlessly for 3 months after I swapped in the TPI.

I also just went outside and it started right up and ran and reved fine. It is like there is nothing wrong now. It has cooled down since I got back from Havasu about 2 hours ago.

Harley

jbbiggs

Pickup coil..............

Hoss50

What exactly is the reluctor? I have never heard of it.

I replaced the pickup coil 3 months ago when I swapped in the TPI. New cap, rotor, module, pickup coil.

I thought pickup coils go bad and that was it. No interminttent.

Thanks
Harley

jbbiggs

I would replace the reluctor and the pickup coil, where did you get it brand name?



In an electronic ignition, a rotating reluctor and magnetic-pickup coil replace the traditional cam, breaker points and condenser in the distributors of cars equipped for electronic ignition. This system reduces the time between tune-ups. The high spots of the reluctor interrupt the magnetic field of the pickup coil and the permanent magnet. These interruptions, or pulses, are transmitted from the pickup to a nearby electronic control unit. There, the pulses signal a transistor to break the low-voltage sub-circuit and release high voltage from the coil to the spark plugs.

razor

The reluctor is not the pick up coil. The reluctor is above the pick up coil. It is attached to the distributor shaft and has 8 sides and is basically a timing disk to pulse current. Take your cap off, then your rotor and look for a slightly rusty piece with 8 sides. This will be your reluctor.

Hoss50

I got it at Autozone, I think the brand is Wells.

jbbiggs

did you check for fire at the plugs when it wouldn't run?
also if you have a noid light you can for injector pulses.
if both do not exist i would say pickup coil, I haven't came across many reluctors cracked but it's possible.

Hoss50

I didn't get to check the fire at the plugs or use my Noid light because I forgot my remote starter at my house so I couldn't turn the key and watch for both since I was alone.

cronsformula350

what is your truck doing right now, what does it do when you crank it, what does the motor try to do? c

code 12 is the normal diagnostic code.

http://www.cardomain.com/id/cronsformula

Hoss50

Now that my truck is cooled of it will start up no problem. I started it last night to move it off the street and into the driveway, and it acted like nothing was wrong at all. Fired right up and acted completely normal.

If I drove it around for 30 minutes it would probably die again.

I am going to get a new pickup coil tonight and reluctor ring if the parts stores sell them and hope that fixes my problem.

Harley