cuzinpete Posted January 30, 2020 Share Posted January 30, 2020 Hi...car is getting a strong spark, no fuel... ignition module and harness, crank sensor replaced...ran for a day...yesterday mechanic put in a new battery, cleaned up connections, and it started up ..then stalled when I got home...won't start this morning...will just crank, and not catch...running out of things to replace that have been replaced already in the last 2 years...could it be the fuel pump? When I turn the key, you can hear the pump humming...I've had the car in the shop 3 times in the last two weeks and I'm running out of ideas...the car has only 102,000 miles on it and I don't want to give up on her...I'm desperate...any ideas would be greatly appreciated...thanx Greg Link to comment Share on other sites More sharing options...
joe_padavano Posted January 30, 2020 Share Posted January 30, 2020 When you turn the key to START, the fuel pump should run for two seconds to prime the injectors. A fuel pressure gauge on the test port will tell you if that is happening or not. You may also be able to hear the pump run if someone is listening at the tank. If you determine there is no pressure, figure out if the pump is actually bad or if there is some reason why it isn't running (like a bad relay or fuse). Link to comment Share on other sites More sharing options...
cuzinpete Posted January 30, 2020 Author Share Posted January 30, 2020 I can definitely hear it...but if I turn the key when the car is cold, I hear the pump run for at least 5 minutes... sometimes it will cut off by then...but once I try and fail to get the engine to start, the pump runs longer when I turn the key, after more failed starting attempts...is that normal? Should it not be running that long? I hope I'm giving enough info...could the pump be bad, or maybe the relay? That's the one thing that hasn't been replaced. Thanx for such a quick response...any advice helps so much. Greg Link to comment Share on other sites More sharing options...
edinmass Posted January 30, 2020 Share Posted January 30, 2020 (edited) It’s a basic OBD I system, which proper diagnostic flow charts will correctly pinpoint the problem......find a small shop with an owner or mechanic that it 50 years old........won’t be too difficult to fix. Swapping out parts and guessing is just tossing money away. Other issues could be bad grounds, prom, or other intermittent issues that will drive you crazy. Hook up a fuel pressure guage and tape it on the windshield so you can see it while driving. Figuring out if the issue is spark or fuel that is dropping out is helpful, as the ignition and injection circuits are separate from each other. (Gives you a great place to start looking.) Figuring out if you have an input, output, main pcm or ground issue should not be terrible. Experienced mechanic is what you need.....not the internet or YouTube.. hang in there, you will get it with the right guy. Back in the day I fixed the crazy computer CRT controls for the A/C and heat........on the fancy models, most of the electronics were more Cadillac than Buick.............it’s too long ago for me to remember the common issues we had with them....... Edited January 30, 2020 by edinmass (see edit history) Link to comment Share on other sites More sharing options...
cuzinpete Posted January 30, 2020 Author Share Posted January 30, 2020 Thank you so much...I will definitely look into this Link to comment Share on other sites More sharing options...
edinmass Posted January 30, 2020 Share Posted January 30, 2020 (edited) Fuel pumps often fail under load and temperature resistance........replacing a fuel filter that is restricted will often cause the pump to fail from changing torque thrust on the brushes. You can jump power to the fuel pump and run it for an hour with the guage hooked to it (car doesn’t have to be running) to see if the pump is shutting off or dropping pressure..............very,very common issue. You should be able to do this yourself at home, don’t take a short cut.......run the guage on it so you can understand what’s happening. Edited January 30, 2020 by edinmass (see edit history) Link to comment Share on other sites More sharing options...
cuzinpete Posted January 30, 2020 Author Share Posted January 30, 2020 Thanx...that's another great point Link to comment Share on other sites More sharing options...
misterc9 Posted January 31, 2020 Share Posted January 31, 2020 Maybe you are hearing the air ride pump running. The fuel pump should not run more than a few seconds without the engine turning over and giving an ignition spark. The fuel pressure gauge is a must for this type of no start. A noid light to test power to the injectors would be another must. Link to comment Share on other sites More sharing options...
cuzinpete Posted January 31, 2020 Author Share Posted January 31, 2020 I had no idea that was the air ride pump...I'm a dummy...lol...I will let my mechanic know everything you guys have told me...this info is invaluable...I'm getting a little piece of mind after stressing out all day over this...thanx so much. Link to comment Share on other sites More sharing options...
misterc9 Posted January 31, 2020 Share Posted January 31, 2020 GMs of this era suffered from bad connections at the harness plug where the fuel sender plugs into the car's harness. This often caused intermittent fuel pump action or no start at all. Most new fuel pump sender assemblies include a new harness plug repair kit to splice in and fix this problem. Link to comment Share on other sites More sharing options...
cuzinpete Posted January 31, 2020 Author Share Posted January 31, 2020 Thanx for that info! Link to comment Share on other sites More sharing options...
Frank DuVal Posted February 1, 2020 Share Posted February 1, 2020 Harbor Freight Fuel pressure gauge would pay for itself. Hard to diagnose fuel pump issues on fuel injection without knowing what the pressure and flow really is. 1 Link to comment Share on other sites More sharing options...
cuzinpete Posted February 11, 2020 Author Share Posted February 11, 2020 Hi...just a quick update...The harness for the ignition module was replaced a few weeks ago...when we tried to start the car, my mechanic tapped on the harness with a screwdriver, and the car started...he replaced the harness...so when I couldn't get the car started again, he checked the module, that was originally replaced last summer, and it was fried...it was covered under warranty, and replaced...car fires up, and engine light is off...so I guess it wasn't a fuel issue after all...thank you to everyone who responded to my question...it's a relief to have some dependability back...well, as much dependability that you can have with a 30 year old car...lol...thanx again. Link to comment Share on other sites More sharing options...
joe_padavano Posted February 11, 2020 Share Posted February 11, 2020 5 hours ago, cuzinpete said: it's a relief to have some dependability back...well, as much dependability that you can have with a 30 year old car...lol...thanx again. My 1962 Olds is the most dependable car I have. There really isn't much of anything to break on it. Link to comment Share on other sites More sharing options...
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