Chevy Engine Starting Problem

[Mark Gibson]

Hello Gentlemen, Hope all is well, been awhile since I have chatted, but I guess thats a good thing, nothing is broke!

Question for you, 1989 Chevy PU, 350, Throttle Body Fuel Injection, GM Electronic Ignition Distributor, with external coil, not HEI with coil built into the cap. Truck has 110,000 mile on it.

Problem is the engine was running ok, and gradually over a few miles began running rough, and quit running altogether. You try to restart, she trys to catch and crank up, but it doesn't. I checked to see if maybe it had jumped timing, but brought #1 around to TDC, pulled the cap, and the rotor button was dead on, and it would turn when cranking. Looking at the injectors in the TBI, they are spraying. Looked at the plugs and they were sooty, not oily. Cleaned them, and used ether/starting fluid spray to try and start the engine, still would not run. Pulled a plug and saw spark, but not sure how hot the spark was. We were in the woods hunting, and didn't have a lot of tools.

Coil has never been replaced, MAPP sensor replaced 10,000 miles or so, ago. Not sure what else to look at or replace. As always, your information will be greatly appreciated!

Thanks Gents!

MG

[idol]

Hi Mark,
If memory serves me, GMC and Chevy trucks used a dual fusible link setup. One link goes to the starter motor and the other to the ignition system. From what you have described, "she trys to catch and crank up, but it doesn't" , sounds very much like the fusible link to the ignition system has fried.
Try this, at your battery, positive (+) terminal look for a 18 or 20 gauge "red" wire that leaves the battery and seems to reappear at the firewall or on either of your fender well covers at a 2-bolt block. These two wires attached to the block are the two "fusible links" I mentioned.
Once you find the two wires, trace them from the block to their appropriate components. Feel each wire for a soft "mushy" place, or even an obvious burned point. If you find it, then replace the wire.
These fusible links cost around $25-30 each. But over the years, I have had many of the similar vehicles such as yours come to me with the same type symptoms, and most often this has been the problem. Especially if you were experiencing any other symptoms prior to this failure. IDOL

[MGibson]

Thanks IDOL for the advice. I know exactly what fusable link you are talking about. I appreciate the reply!

MG

[idol]

Let me know what you find out Mark....Idol