Stalling from fuel loss?
Ok Im new to this forum but really confused about what my truck is doing. I have a 1995 GMC K1500 4x4 Z71. About 3 weeks ago my fuel pump went out on my truck. I removed the tank removed the old fuel pump and replaced it with a new one. I cleaned my tank really good before installing the new one. I also replaced the fuel filter on the frame under the driver door. About a week ago it started acting all kinds of crazy. At start up when cold it runs like a top for about 1 to 2 miles. Once the engine gets heated up it starts spitting and sputtering. If you baby the gas it goes on but still cutting out. If you cram it to the floor it picks up fuel and goes on like a top but then when you let off it then it goes back to the spitting and sputtering. My son put it on a ob1 scanner and it registered the code for the EGR but he said he didn't think that was happening because he took my EGR out and looked fine and he could even blow through it and it wasn't stopped up. So I took it to a local shop here and had it put on a machine and they informed me it was the map sensor so I changed that. Still doing the same thing. However when you unplug the map sensor it runs like a top at idle and in drive/reverse with my foot on the brake. I was standing there when they put the fuel pressure gauge on it and at start up/ idle/ and in drive it registered 10 psi. It never changed. The shop told me if the map sensor didn't fix it then it could be the computer. I just don't really believe that. I truly feel it would be another sensor somewhere that the shop missed. After it warms up if it is sitting idling it runs rough as crap and then dies. Once it dies I smell some nasty fart smell or something rotten. I am so confused with all this. Sometimes my service engine light will come on and when it does my truck runs like a top but when it resets itself it starts running rough again like it losing fuel. Just today on the way to work it sat and idled for a few minutes and started running a lil warm from where it usually runs. Could all this be caused from a coolant temp sensor. I am so confused with all this crap. I HATE SENSORS!! Anyones help would be appreciated. Thanks Tam
You didn't mention the engine size so I am assuming it has a 5.7 vortec. Fuel pressure should be 50 psi at idle, I am surprised that it even runs with 10 psi. If this is not your engine please re post here with more info.
yes my truck is the 5.7 but it is throttle body not votec.
OK so that should be 9 to 13 lbs, so 10 at idle is good but it should jump up when the throttled is goosed, also you should not be able to blow through the EGR valve when it is off the engine, if you can it is leaking and that will cause a running problem and a strange exhaust smell and turn on the check engine light, double check the EGR valve, make sure it is closed, recheck the codes as it is an OBD1 GM they are easy to get the codes from just using a paper clip. Go to: http://www.youtube.com/watch?v=V8nZpQyoRh4 After that is done if you can't find the code reference re-post back here and we will go from there.
I got it hun thank you. i figured it out by unplugging each sensor. it was the o2 sensor and i also had a ground wire broken from the block to the frame. fixed all that and she runs like a top again. thanks for all your help though. and the paper clip video was awesome and very helpful. love it. thanks tammy
Tammy were ur truck cutting off ?
When u put it n reverse r drive
Looking for a Used Sierra C/K 1500 in your area?
CarGurus has 2 nationwide Sierra C/K 1500 listings and the tools to find you a great deal.
Search GMC Sierra C/K 1500 Questions
GMC Sierra C/K 1500 Experts
Related Models For Sale
Used Cars For Sale