20 Most Recent 1992 Chevrolet K1500 - Page 3 Questions & Answers

There are a number of different problems that can cause rough idle. These are a few. Test fuel pressure, check timing, Will dropping into neutral save it from dieing? torque converter may be going bad.

Secondary Air Injection System Malfunction

spark knock (detonation ) is caused from incorrect air/fuel / spark timing. It is spontaneous combustion. IT cam be overcome by filling with a higher octane rated petrol, changing gears more often and not bogging down in the rpm.s will eliminate a lot of it . Run the fault codes and check for problems in the O2 sensors , MAF/MAP sensors and check that the air filter is clean.

If the vehicle has a automatic transmission, check the Neutral Safety Switch. If defective from wear it could be sending incorrect signals to the Electronic Control Module which in turn sends signals to the Idle Air Control. It will make the computer think the transmission is in gear and lower the RPMs and then when the transmission is actually in gear the physical load will lower the RPMs even more. To check, set the parking brake and move the gear selector to Neutral and check the RPMs to see if the engine maintains a constant 650 +/-. Next, shift to Drive and check if RPMs drop to and maintain 500 +/-. If it does then you have diagnosed the problem. The original equipment Idle Air Control motors rarely wear out.

Hi, try installing a relay to supply current to the pump, you might have to install a new off/on switch to activate pump with relay(safety measure). Hope this helps with problem.

you said you tried applying direct voltage to the pump? proceed to remove the fuel tank and check the harness inside for continuity, both wires going to the pump itself. If wires prove to be ok , then proceed to replace pump .

Remove the battery cable & see if it will relearn the shift points I doubt a 1992 even has that capability,you may have a failed trans

does it happen if the injectors are unplugged ? could be a problem with the gasket or seal for the injector.

Sounds like a battery connection,try this ,turn the headlights on,have someone watch or whatever,try to start it,if the lights go out,it's a poor connection(probably at the battery) if they stay on,it's a starter issue.

This may sound silly but I had the same problem with my own truck but try and change your t.p.s.Thats what I did and it worked

check your crankcase breather .may need cleaned.so have back pressure.

check coil and distributor for output