Truck Has No Power

[Krafty]

have you done a fuel pressure test? lack of vacuum at the Fuel Pressure Regulator will cause a fuel pressure spike.

 

[budster 95]

Yes Krafty is right, usually when someone uses the term "back firing" they mean though the exhaust. But if its through the intake it does still sound like a timing, or valve problem. Also a lean condition can cause popping through the intake. Good luck.

 

[91bronco94motor]

When I did the fuel pressure test I had 35 to 40 lbs of pressure I think I would have to test it again to be sure one of the things that I noticed today is I put it in 4 wheel high and it felt like it had triple the power don't know what that means

 

[budster 95]

did you have the distributor out at all?

 

[91bronco94motor]

I have not but that's not saying the guy i got it from didn't i double checked the timing and its set to 10 btc like it says with the spout connector off

 

[budster 95]

I wonder if its off one tooth. Do you know how to find TDC?

 

[budster 95]

If its one tooth off (too far advanced), the spark plug ignites with the intake valve still open. this causes popping through the intake.

 

[91bronco94motor]

ok i will take it out tomorrow an put it back in and see what that does thanks

 

[budster 95]

Your welcome, let us know how you made out. Hope that works for ya.

 

[Bully Bob]

Did anybody mention the timing chain...? (didn't read the whole thing)

A tooth off on the dizzy can be made up by turning the dizzy adv. or ******.

Not so with a bad timing chain/gears.

 

[budster 95]

TDC on #1 piston with both valves closed will confirm correct valve timing, (timing chain is good). Then drop distributor back in with rotor pointing to #1 plug wire. If you find a valve is open at TDC, this will tell you your timing chain has jumped. The timing chain has dots on the gears that need to be lined up at installation, to ensure correct valve timing with the crankshaft. After reading that you have checked compression, this tells me that your valve timing is correct. Because you would never have those readings if a valve was open on compression stroke.

 

[91bronco94motor]

All of u are going to think that I'm a DA but I looked in to a timing problem and I read the book wrong on the firing order I used a 302 firing order in the book and yhe firing order for a 94 and above is different than just a 302 thanks for all the help now all I have to do is rebuild the transmission because the overdrive us out on it

 

[budster 95]

Bet you wont make that mistake again anytime soon. Glad you got it. Happy trails

 

[Elmo]

I like to write the correct fireing order on the underside of the hood so i always have it