Fuel pump? (Page 1/2) saving_rossi SEP 14, 09:26 PM I have recently done a lot of work to my fiero. The owner before me had a mechanic do some work as well. My problem recently is intermittent stalling, only when the engine is warm and only right after starting it up. And when I do start it up, it starts up very quickly. It doesn’t smell of fuel and it is not leaking. When I prime the fuel pump, it is very audible and sometimes has crackling sounds. I was told by the previous owner that he had replaced the fuel pump. When I had issues with fuel delivery, I replaced the injectors and the fuel regulator. My current thought is to replace the fuel pump and filter because I can’t think of what else it could possibly be. Reaching out on the forum for other opinions, to see if I’m missing anything. Patrick SEP 14, 09:49 PM quote Originally posted by saving_rossi: My current thought is to replace the fuel pump and filter... What is the fuel pressure when the engine is running? How long does the fuel pressure hold when the engine is turned off? jelly2m8 SEP 15, 04:00 AM 2.5 or 2,8? This matter alot. Never EVER put much faith in a previous owners thoughts, there is a reason they sold it after all..... jelly2m8 SEP 15, 04:02 AM 2.8? Auto? typical either Ignition module or TCC solenoid failure..... Mike in Sydney SEP 15, 04:53 AM quote Originally posted by Patrick: What is the fuel pressure when the engine is running? How long does the fuel pressure hold when the engine is turned off? Take it from me, listen to Patrick. Check your fuel pressure and how long it holds pressure after you turn the car off. My ‘86, 2.8L, V6 was giving me similar problems. I changed all the sensors, the TPS, MAP, etc. I “knew” it couldn’t be the fuel pump because I had installed a new one and I could hear the pump prime when I turned the car on. I was at point of replacing all the injectors. When my mechanic checked everything, he found low fuel pressure an a couple of intermittent vacuum leaks on some rubber connectors. The “new” pump was replaced with another new pump and the vacuum leaks corrected. Problem solved. Not saying this will fix yours but before you start tossing money at the problem, check the simple things first. saving_rossi SEP 15, 03:10 PM quote Originally posted by Mike in Sydney: Take it from me, listen to Patrick. Check your fuel pressure and how long it holds pressure after you turn the car off. My ‘86, 2.8L, V6 was giving me similar problems. I changed all the sensors, the TPS, MAP, etc. I “knew” it couldn’t be the fuel pump because I had installed a new one and I could hear the pump prime when I turned the car on. I was at point of replacing all the injectors. When my mechanic checked everything, he found low fuel pressure an a couple of intermittent vacuum leaks on some rubber connectors. The “new” pump was replaced with another new pump and the vacuum leaks corrected. Problem solved. Not saying this will fix yours but before you start tossing money at the problem, check the simple things first. This sounds exactly like my problem…I’m having vacuum leaks too. I just did a fuel pressure test and it went to 40psi, and it very slowly went down to like 15psi and is holding that pressure. Patrick SEP 15, 03:21 PM quote Originally posted by saving_rossi: ...and it very slowly went down to like 15psi and is holding that pressure. We may have different definitions of "very slowly". Did the pressure start to drop from 40psi immediately? How long did it take to get to 15psi? saving_rossi SEP 15, 04:15 PM quote Originally posted by saving_rossi: This sounds exactly like my problem…I’m having vacuum leaks too. I just did a fuel pressure test and it went to 40psi, and it very slowly went down to like 15psi and is holding that pressure. Also I’ve got a 85 2.8 auto saving_rossi SEP 15, 04:46 PM quote Originally posted by saving_rossi: This sounds exactly like my problem…I’m having vacuum leaks too. I just did a fuel pressure test and it went to 40psi, and it very slowly went down to like 15psi and is holding that pressure. Also I’ve got a 85 2.8 auto saving_rossi SEP 15, 04:49 PM quote Originally posted by Patrick: We may have different definitions of "very slowly". Did the pressure start to drop from 40psi immediately? How long did it take to get to 15psi? Took maybe 30 minutes to get to 15 psi, but it only took maybe 30 seconds to drop to 25 psi. and it actually continued dropping after 15... its been maybe two hours and now it’s at like 3 psi?