87 ranger

[zdewald]

ok so my 87 ranger with 2.9l and it runs fine but if you go to pass a car or something and you hold the pedle to the floor its fine untill you back off the gas and hold it about half throtle. it starts shacking and running very ruff. but if you hole it to the floor or take your foot right off the gas its fine. otherwise it runs ruff for a little bit than starts running smoth again. so couls someone tell me if this could be the map sensor or something?

 

[IMenriched]

ok so my 87 ranger with 2.9l and it runs fine but if you go to pass a car or something and you hold the pedle to the floor its fine untill you back off the gas and hold it about half throtle. it starts shacking and running very ruff. but if you hole it to the floor or take your foot right off the gas its fine. otherwise it runs ruff for a little bit than starts running smoth again. so couls someone tell me if this could be the map sensor or something?

well for starters, what codes are present??
look for vacuum leaks

 

[zdewald]

the only code i get is the egr valve and iv looked and theres no valcuum leaks

 

[IMenriched]

the only code i get is the egr valve and iv looked and theres no valcuum leaks

Has the fuel filter been replaced??
recheck the timing
what kind of fuel pressure is there, should be 30-40psi
run a compression test, maybe you got a weak cylinder, or vacuum check
check for loose wires and or poor connections

 

[zdewald]

fuel systems all new has around 30 psi. engine was rebuilt about 10000 miles ago. it has no valcum leaks.
it only dose this when u r going 55 and u hold it to the floor and get it up to about 80 than backoff to about half throtle. when u do that it runs ruff for a little bit than is fine

 

[kimcrwbr1]

take the egr off and clean it good with carb cleaner press it in and see if it is sticking. get a gasket first to put it back together see if that works. if that is the problem I would buy a new one for when it does it again

 

[zdewald]

erg valve is fine it has nothing to do with the problem i bought a new one and all that and it still did it

 

[off_road_junkie21]

map sencer!!

 

[zdewald]

that is what i was thinking it was. is there anyway i can test it or should i buy a new one or just not bother with it and leve it be?

 

[IMenriched]

that is what i was thinking it was. is there anyway i can test it or should i buy a new one or just not bother with it and leve it be?

this may be helpful to that end.
http://www.fordfuelinjection.com/?p=27