1990 f150 Wont Start
#47
Ok guys...here's something really weird. I pulled out all the spark plugs and turned it over (just to make sure it wasn't flooded) then put all the plugs back in and did a compression test...it barely lifted the needle, pretty much 0 psi!!! Wtf. I know the engine is cold but it shouldn't be reading that low. What could have happened?
Edit: just did a compression test on two more cylinders and got 55 and 40 psi. So the readings I got were: 1-40 psi. 5-0 to 5 psi. 6- 55 psi.
Tanner
Edit: just did a compression test on two more cylinders and got 55 and 40 psi. So the readings I got were: 1-40 psi. 5-0 to 5 psi. 6- 55 psi.
Tanner
#49
The timing chain has some slop in it. Not a ton but you can turn the engine one way and then the other and it takes a second for the rotor to respond. Also when I pulled out the plugs they were wet. I just read online if your engine floods it can cause you to lose compression. Something about washing out the cylinder walls. I'm pretty sure it was flooded when I first tried starting it because the injectors leaked. But I got the leak fixed by putting in new injector o-rings and itll hold 35 psi fuel pressure
Tanner
Tanner
#50
More than likely you washed the cylinders. Take oil and spray in each cylinder as you check each one. The psi should come up.
when you and your uncle moved the timing to 10*. Did you do it while cranking or did you move the crank to 10 then check # 1 piston position and dist position on tower #1?
when you and your uncle moved the timing to 10*. Did you do it while cranking or did you move the crank to 10 then check # 1 piston position and dist position on tower #1?
#52
How I do it is ...disconnect battery. Grab a socket and pull motor around to 10* BTC put screw driver on #1 hole it should be at TDC. Look at dist...should be at #1 tower. From that point you should be ablt to start truck IF it was out of time. When started you should be able to adjust from that point.
#53
#54
Ok guys...here's something really weird. I pulled out all the spark plugs and turned it over (just to make sure it wasn't flooded) then put all the plugs back in and did a compression test...it barely lifted the needle, pretty much 0 psi!!! Wtf. I know the engine is cold but it shouldn't be reading that low. What could have happened?
Edit: just did a compression test on two more cylinders and got 55 and 40 psi. So the readings I got were: 1-40 psi. 5-0 to 5 psi. 6- 55 psi.
Tanner
Edit: just did a compression test on two more cylinders and got 55 and 40 psi. So the readings I got were: 1-40 psi. 5-0 to 5 psi. 6- 55 psi.
Tanner
You'd want it WOT all plugs out while doing so if by chance you had not done so, zero or very little air in would effect those readings.
Based on what you've stated no it does not sound like its jumped time.
As suggested put teaspoon of oil down each plug hole and retest, remove fuel pump relay to be sure no fuel is injected during compression testing see if values come back up to normal.
If value doesn't come up you're gonna have to look into valve timing, see if it did jump time.
#55
#1 piston is at tdc when I'm at 10° or 0°. So that's another reason I think my chain didn't jump time. So I have no idea why I lost so much compression...sadly I didn't have a compression tester when the truck was running, so I have no idea where it was, but it ran good.
Tanner
Tanner
#56
#57
Hey guys..good news. I pulled out all the old plugs and poured a little oil in the spark plug holes. Let it sit a little bit and installed new plugs. Tried cranking it and it is hitting really hard now! It really wants to start. It also was bellowing white smoke out the pipes. It is close to starting now. I think I'm finally seeing some light at the end of a long tunnel.
Tanner
Tanner
#58
White smoke is unburned fuel.
Sounds like your fuel injectors are open all the time. Maybe the wires to the computer from the fuel injectors is shorted to ground. Could also be a bad computer with shorted transistors for the fuel injectors.
It also sounds like you plugged the computer back in without getting it running on starting fluid.
Sounds like your fuel injectors are open all the time. Maybe the wires to the computer from the fuel injectors is shorted to ground. Could also be a bad computer with shorted transistors for the fuel injectors.
It also sounds like you plugged the computer back in without getting it running on starting fluid.
#59
White smoke is unburned fuel.
Oh ok I figured it was the oil I put in there
Sounds like your fuel injectors are open all the time. Maybe the wires to the computer from the fuel injectors is shorted to ground. Could also be a bad computer with shorted transistors for the fuel injectors.
Hmm..I'll try finding a PCM to swap over.
It also sounds like you plugged the computer back in without getting it running on starting fluid.
Oh ok I figured it was the oil I put in there
Sounds like your fuel injectors are open all the time. Maybe the wires to the computer from the fuel injectors is shorted to ground. Could also be a bad computer with shorted transistors for the fuel injectors.
Hmm..I'll try finding a PCM to swap over.
It also sounds like you plugged the computer back in without getting it running on starting fluid.
Tanner
Edit: messed up on the quoting ^ my replies are in the blue box..lol