Won't start when hot, '92 V8 Dakota
 

Greetings. I have a '92 Dakota V8 4x4. 200,000 miles. Had to replace the fuel pump about 6 months ago, but usually a good strong truck. Last week I was 5 miles from home and it died on the highway. 20 minutes later it started right up and ran great. Now it keeps doing that. Sometimes dies before I get where I'm going. Starts right up when cold but will not start when hot. Turns over strong, but won't fire. Any ideas what to check?

RE: Won't start when hot, '92 V8 Dakota
 

Check the MAP sensor. That sounds like what happened when my MAP sensor went bad.

RE: Won't start when hot, '92 V8 Dakota
 

I know what and where a MAP sensor is, but how do you "check" a MAP sensor?

RE: Won't start when hot, '92 V8 Dakota
 

To test:
(1) Inspect rubber L-shaped fitting from the MAP sensor to the throttle body. Repair as necessary.
(2) Test MAP sensor output voltage at the MAP sensor connector between terminals A and B (picture provided). With the ignition in the ON position (and engine OFF), output voltage should be 4 to 5 volts. The voltage should drop to 1.5 to 2.1 volts with a hot, neutral idle speed condition.
(3) Test PCM (powertrain control module) cavity A-27 for the same voltage described above to verify the wire harness condition. Repair as necessary.
(4) Test MAP sensor supply voltage at sensor connector between terminals A and C with the ignition ON. The voltage should be appx. 5 volts (+/- 0.5 volts) Five volts (+/- 0.5 volts) should also be at terminal A-17 of the PCM wire harness connector. Repair or replace the wire harness as necessary.
(5) Test MAP sensor ground circuit at sensor terminal (A) and PCM connector A-4. Repair the wire harness if necessary.

There are 3 connectors for the PCM. IIRC, connector A is the one in the front. The pins should all be marked on the inside of the connector.

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RE: Won't start when hot, '92 V8 Dakota
 

Also heat sensitive coil, pickup assembly in distributor or crankshaft position sensor.
http://dodgeram.info/tsb/1992/18-04-92.htm