backfire and huge miss

[flowranger]

i was driving my truck one night and it was running fine. i start it up the next morning and it misses so bad the whole engine shakes and its backfireing like crazy. it has no power at all. could it have jumped time on startup? is there anyway to tell without pulling the waterpump and such? or is there anything else it could be?

 

[IMenriched]

one can check base timing ...remove spout plug....get timing light, start engine. should be on 10deg TDC.

before one gets crazy and goes after the timing chain. do a good tune up 1st. plugs, plug wires, cap and rotor. check the TFI or AKA ignition module.

not to say it couldn't the timing chain, just it is very unlikely.

 

[flowranger]

It has just had a tune up could the tfi cause this I just re placed it about a month ago

 

[IMenriched]

yes the tfi could do this I had 1 go south with in 50 miles.

also when was the lastime you had changed the fuel filter??? and check the FPR

any codes present?

 

[flowranger]

no codes present
fuel filter was part of tune up.
no gas in the fpr vacuum hose

 

[IMenriched]

Double check for loose connections & battery cables and grounds. look for poor vacuum lines and connections as well.

did you have to adjust timing after the last "tune up"???. by retesting the base timing you'll verify it is still OK, or not...sometimes the hold down on the distributor after setting timing don't get retightened.

may want to get a fuel pressure guage on it, make sure the pumps are up to snuff.

 

[flowranger]

Fuel pressure is fine and timing was double checked I'm going to have the tfi tested today

 

[sniper141]

I had an issue like that with my expedition after I had detailed the engine. One of the plugs got soaked and wasn't firing until I drove it to work after it being warmed up, it dryed it up and started and ran fine afterwards. It had the exact same symptoms that you are explaining.

 

[flowranger]

i have switched plugs out and wires it does not help. it runs like this constantly

 

[Psychopete]

i have switched plugs out and wires it does not help. it runs like this constantly

Sounds like you might have a nasty vacuum leak (I forgot once to hook up the vacuum line from the gas fume canister to the bottom of the TB and it idled like a top fuel dragster), or you might go through a compression check to make sure you don't have an intake valve that can't close. Might be hard, but I would be tempted to try and isolate it down to a specific cylinder.

Pete

 

[flowranger]

it has 130 psi on 4 cylinders 120 on 1 cylinder and 140 on the other. i cant find any vacume leaks.
also it is backfiring out the intake and exhaust.

i will look over everything again tomorow. i am also getting new wires and having the tfi checked

 

[flowranger]

tfi is good new wires helped the missing but it still backfires. my dad who is a mec thinks it maY have a dead lifter or 2 because the previous owner replaced them after it flattend a few out in a mud hole and they did not replace the cam

any suggestions? im gonna tear it down tomorrow and ckeck everything out

 

[IMenriched]

tfi is good new wires helped the missing but it still backfires. my dad who is a mec thinks it maY have a dead lifter or 2 because the previous owner replaced them after it flattend a few out in a mud hole and they did not replace the cam

any suggestions? im gonna tear it down tomorrow and ckeck everything out

sadly that is the best approach....and you may very well find it is the timing gear/chain issue. or a broken cam , be it highly unlikely.

but concidering the new info of this thing swallowing a slug of mud in the past....look it over very closely. Might be good time to upgrade to 4.0??

 

[flowranger]

well it is perfectly in time. and when i had the valve covers off each rocker arm seemed to be moving like it should.

filled it up with gas today and the miss went away altogether but still lacks power... im going to drive it some tomorow and see if it runs better... im thinking that eather the fpr or a fuel pump may be going out... im gonna see if i can get a fuel pressure gauge and check it out b4 i tear everything down..



if i had the time/money i would do a 4.0 or 5.0 swap in a heartbeat. but my mom is funding all repairs so what she says goes.

 

[Frank The Tank]

Bad gas? it can happen.........
was there a weather change over night? excessive moisture in air?
I mean... it ran fine, shut it off. ate a sandwich, went to bed.... came outside the following day and it immediately ran like this??

btw, it's a 2.9 it's gonna be low on power, lol.
couldn't resist.... 88 t'was a good year.

Frank