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skizzik · 06-13-2010, 10:48 AM

Status update -

I fixed the SES light and pulled codes 24 (vehicle speed sensor), 33 (MAP sensor), and 44 (lean exhaust). These codes must have been stored in the ECM for a long time because my battery hadn't been disconnected in a long time. I noticed the Throttle Position Sensor and the end of the throttle shaft that it sits against were gunked up so I cleaned the area and put in a new TPS and then disconnected the battery for a few minutes to clear all codes and then went for a drive. It didn't stall while I drove but now it's running really rough at lights and the idle sounds really high when I switch to neutral or park. Pulled codes when I got home and picked up error 33 again (MAP sensor).

Thoughts?

Replace the MAP sensor? Is it possible the previous owner tried fixing the stalling-at-lights problem by turning the idle up too high and now all I need to do is turn the idle down? I should point out that all I did for the new TPS was stick it on. I was just reading online that many Throttle Position Sensors require initial adjustment - should I have done that?

06-13-2010, 10:48 AM	#13
skizzik Registered User Join Date: May 2010 Location: Austin,TX Posts: 35	Re: '87 R10 suburban 350 V8 TBI stalls at lights - suggestions? Status update - I fixed the SES light and pulled codes 24 (vehicle speed sensor), 33 (MAP sensor), and 44 (lean exhaust). These codes must have been stored in the ECM for a long time because my battery hadn't been disconnected in a long time. I noticed the Throttle Position Sensor and the end of the throttle shaft that it sits against were gunked up so I cleaned the area and put in a new TPS and then disconnected the battery for a few minutes to clear all codes and then went for a drive. It didn't stall while I drove but now it's running really rough at lights and the idle sounds really high when I switch to neutral or park. Pulled codes when I got home and picked up error 33 again (MAP sensor). Thoughts? Replace the MAP sensor? Is it possible the previous owner tried fixing the stalling-at-lights problem by turning the idle up too high and now all I need to do is turn the idle down? I should point out that all I did for the new TPS was stick it on. I was just reading online that many Throttle Position Sensors require initial adjustment - should I have done that? Last edited by skizzik; 06-13-2010 at 11:38 AM.