egr
#1
12-30-07, 10:26 AM
egr
Hi all,
I have a 1990 GMC Jimmy full size, 5.7, TBI, Auto trans, 170k milage. The check engine light came on with a code 32 (EGR). I placed a vaccum guage in place of the EGR and no reading. I checked manafold vac and all is well. Next I probed the EGR Vac control leads with a test light. Jumping the plug no result. Taking one lead to ground and I have power. Put the ADL into diagnostic mode and the connector rings through. To me this would indicate a bad ECM. What are your thoughts? If I change the module should i also replace the PROM? Thanks Ol Blu
I have a 1990 GMC Jimmy full size, 5.7, TBI, Auto trans, 170k milage. The check engine light came on with a code 32 (EGR). I placed a vaccum guage in place of the EGR and no reading. I checked manafold vac and all is well. Next I probed the EGR Vac control leads with a test light. Jumping the plug no result. Taking one lead to ground and I have power. Put the ADL into diagnostic mode and the connector rings through. To me this would indicate a bad ECM. What are your thoughts? If I change the module should i also replace the PROM? Thanks Ol Blu
#2
12-30-07, 10:31 AM
Have you replaced the EGR, yet? It seems to be the culprit. No need to go replacing items not at issue. Does the EGR diaphragm move up and down as you rev and release the engine? Can you manually move the diaphragm up with a finger? If not, replace it. Check also once you have it off, all the carbon deposits. Have a vacuum cleaner available when you chip all the carbon deposits from the intake, as you don't want them to be ingested in the engine.
#3
12-30-07, 11:07 AM
egr
Thanks Larry,
The ERG is not getting Vacuum. I removed and cleaned the valve and applied manual vacuum and it works. I rang out the vacuum controller, i.e. applied power and I can draw vacuum through it.
The ERG is not getting Vacuum. I removed and cleaned the valve and applied manual vacuum and it works. I rang out the vacuum controller, i.e. applied power and I can draw vacuum through it.
#4
12-30-07, 11:23 AM
Your vacuum comes from the back of the throttle body, or directly from the intake. I know you have already checked the hose. Probe into the orifice where it attaches to the intake as there may be a carbon build up in it as well.
