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Hey everyone i recently swapped out my 302 in my 1995 <NOBR style="FONT-FAMILY: inherit; COLOR: darkgreen; FONT-SIZE: 100%; FONT-WEIGHT: normal" id=itxt_nobr_1_0>f150</NOBR>. In the process of swapping it i came across a set of 1969 351w heads (dooe) and decided to put them on the 302 that i put into the truck. Also i had a plenum and intake from a mustang cobra svt (gt40). well long story short now it runs but at around 1200rpm it acts like the engine has a miss and runs rough. do i need to bigger injectors? thanks in advance for all the help
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well long story short now it runs but at around 1200rpm it acts like the engine has a miss and runs rough. do i need to bigger injectors?
No, and even if the motor did it wouldn't need them at any engine speed below 5000rpm, so you have some other problem. Pull the codes and check for vacuum leaks, check the plugs and wire too.
Plugs are new. Wires have around 60,000 miles on them along with the distributor cap and rotor button. The only code that is tripping is HEGO. Heated exhaust gas o2 sensor running too lean...
Plugs are new. Wires have around 60,000 miles on them along with the distributor cap and rotor button. The only code that is tripping is HEGO. Heated exhaust gas o2 sensor running too lean...
Yea that would tend to go along with the vac leak suggest you check for and your high idle condition.
To much air = high idle and depending on how bad a vac leak a lean condition.
Double check your work, you probalby just missed a vac line, or have a intake leak sucking air.
60k on wires cap and rotor? time to replace that stuff.
How old is the 02 sensor? If you don't know its probably time for a new one of them too. However replacing it won't correct your problems, just work better.
If it was a code 172/173 then that's not the right interpretation of the code definition, the correct interpretation is that the engine is running lean as indicated by the HEGO, chances are there is nothing wrong with the sensor otherwise the computer wouldn't know if the engine was lean or rich. And a lean stumble would have been my first guess at your problem anyway, now the problem is finding out what is causing it. It could be a vacuum or intake gasket leak, could be a leak in the smog tubing(if it's still present) or the exhaust upstream of the O2 sensor(cracked manifold), or it could simply be that your replacement motor moves a bit too much air for the stock electronics to handle.. but if the truck is mass air this isn't likely. Was this a stock truck engine you put in?
Alright so i unplugged 2 of the injectors and nothing happened so i put 2 new ones in and it took the HEGO code away the only codes left are thermactor air system and insuficiant rpm range. There isnt any smog pump on this truck so im pretty sure the first one isnt a problem.... but i cant figure out the other one...