| Re: 93 LT1 Starts then dies whenn hot |
Subject: Re: 93 LT1 Starts then dies whenn hot by vettebigguy on 2008/8/23 17:07:49 40652 check no start. After engine runs for 20-30 minutes, it dies and will not restart, until it sits, for several minutes. Then will start and run for a few minutes and repeats the cycle. Check for spark, has spark. Check for fuel, pressure is at 40-45 pounds. Check for INJ pulse, there is no INJ pulse when engine will not start. Check codes, none stored in ECM, CCM,(BCM) has a history C0041 for no com with ECM stored. Cleared code to see if it would reset. It does reset when engine cranks and will not start. Test CCM for power inputs grounds all are OK. Voltage drop on B+ is about 200 mv, about 125 mv on B- side. Readings are the same when the engine runs. Intermittently CCM looses communication when eng won't start. Follow diag chart for C0041. Test comm circuits from CCM to ECM, all are okay, no shorts or opens. Tried a known good CCM engine still has same problem. Tested B= and B- to ECM all okay, similar to readings for CCM. Test all relays and loads on quad driver circuits to see if a component is shorting when hot, and shutting the ECM down.All readings are under the maximum allowed of 750 MA. Check signal for high and low RES crank sensors with a lab scope, both look okay when cranking and engine won't start. Captured data with tech2 and reviewed data. All readings appear to be within normal ranges. This is the report I got from the Gm dealership, of what they have done. This is the sum total of I know to have been done. This is copied right of the work report. Yeah, Blade_1 you aren't the first one to mention getting money back..... Makes a guy wonder sometimes, they are there for the initial sale, but afterwards?? They told me that GM has Tech support for only 10 years then they throw out the info?? Is that right? Holy, they could throw that sort of stuff in MY garbage can..LOL !!Thanks guys, I hope you can shed some light on this for me...cheers for now.. |
