Hello.
90 F150 302. It seems to be flooding out. I can get it to start and run with starting fluid when the fuel pump relay in out. Get it running and plug the relay in and she dies right away. Fuel pressure is 42-45 and stays pressurized for a long time. So I don't think injectors are leaking. SUBFORD had talked about purge valve stuck open in one post dumping fuel. Where is this? Is there a way to bypass and prove it's that? The FPR vac removed is dry. New plugs. Good spark. Any thoughts?


Thanks!

 

Oh one more thing. Brought thought maybe the temp sensor was telling it was very cold so we pulled the connector and shorted the pins. Someone told him this would tell the PCM that it's hot and not to send so much fuel. It did noy help.

 

I have been reading more post on here. TPS, coolant temp sensor. I will check these more throughly this weekend. I have pulled the plugs many times. They were not wet enough to lead me to believe it was flooded that bad. But everything points me to that.

 

TPS is putting out 1vdc (1.024) and I can slowly open throttle and it reads up to 4 vdc. It seems to be right on with what teh haynes manual says. So does the coolant temp. it's putting out 3vdc on a 70 degree truck. Fuel pressure is very solid 42-45. Is that to high? FPR is not lealing.

 

has it been sitting for a while? Bad gas could cause your symptoms. Are you grounding the fuel pump when testing the fuel pressure? If you aren't, then it might be a bit high. My '88 has around 35 pounds. Also check that your spark is strong and not blue. When was the last time you put injector cleaning fluid in the tank and changed you fuel filter? Do you have duel tanks? If so, have you tried changing tanks.

 

Thanks. It has been sitting for 3 months. I can get it to run for 20 second sometimes. Usually when it's been sitting for two days. I thought of gas. do have duel tanks. Front tank was empty. (leaks) I added 5 gallons of fresh 93 oct. in that tank. Both in tank pumps have the same 45 pounds of pressure. I believe i read the injectors are 19 pound. I pulled the fuel rail on the driver side and cranked it over. All four were nice cone shaped sprays. Cranks very slowly. New starter. New battery wires. Neg line was terrible. 2 gauge. Spark looks good to me. (rookie) Blue arc. Seems to me I have everything. Timing. Spark. Air. Fuel. I tried a diff coil. Have new (junk yard) dist. w TFI. Old dist had half a tooth broke. I though it jumped time and changed chain. It was in time when replaced but I think it needed to be replaced anyways. New plugs. Truck is for my son. Seems like it has low spark or is flooding. Runs with starting fluid and fuel relay removed. Brother says it's flooding. He put spark tester deal on it and it sparked orange in that. My was blue when I grounded to block. Now when I start with starting fluid I have to have the pedal all the way down.. shuts off the injectors. I'd love it to be the FPR reading to high. Everyone on here talks about pulling vac line off and see if it leaks. It does not.

 

missed some questions. Sorry.

Not added injector clearer or fuel fitler or grounded pumps. I think your 88 had high pressure pump on rail and that changed in 90 to in tank. I could trace the wires and try to clean the grounds. I cleaned the grounds on the block (replaced) By the battery. And on driver's fender.

 

Back track my work. Upper timing gear dot at 6 o'clock. Lower smaller gear at 12. That seemed very easy to me. Checked compression. Not running have about 100 pounds. Waited till #1 shot the compression gauge up and stopped cranking. Then set time w spout removed at 10 btdc. Set dist to point at #1.

 

its your coil. blue spark is no good. flooded spark plugs will be a symptom of this. Also, have you thought about the alternator when the truck shuts off? Getting it tested is free. You can get a coil for 30 bucks.