98 eddie bauer idles bad at start up

[bonz1234]

My 98 starts up u have to hold the gas pedal for a minute then it will idle by it's self when it warms up u stop at a light it will go down to about 700 rpms then it starts jumping up and down
put a new iac,tps on it no error codes was thiking of cleaning map and throttle body any one have any extra tips

 

[rabbit91]

Cleaning the MAF might do it. New plugs and wires wouldn't hurt

 

[koda2000]

if you have the SOHC 4.0L engine, you probably need to replace your intake manifold gaskets/o-rings. the rough/low idle on start-up is very common in this engine and is due to vacuum leaks caused by bad o-rings. once the engine warms up it typically tends to idle better.

 

[bonz1234]

did u replace your o rings and how log did it take to do the job

 

[koda2000]

Did u change your o rings and how long did it take you

yes. it probably took me about 4 hours, but i work pretty slowly. the o-rings are the part that typically cause vacuum leaks. when they get old they get stiff, brittle and shrink. the parts swell a bit once they warm up and seal better. as i recall there's a manifold bolt at the back that's a bit challenging to get at. i think i ended up using using a long 1/4" extension and a u-joint thing. BTW, it's a great time to change your PCV valve, and check your vacuum hoses and elbows. make sure you get a Motorcraft replacement, as the cheap ones can make noise and don't fit the plastic "T" fitting very well.

 

[vroomzoomboom]

^^^agreed. i think i have done two of them (on different trucks that i have bought to sell) and every time the idle problem cleared up.
with that one bolt i used a 1/4 socket taped to a torx screwdriver bit. also to make more room for yourself, unhook the bulkhead connecter from the computer on the firewall and lay it to the side. it make life much easier. the first one i did took about a hour and a half, the second one took 45 min. its not that hard to do, and you dont have to drain any coolant either

 

[bonz1234]

do you remember the torque specs for the bottom and the top and what pattern manual is sketchy

 

[koda2000]

13 ft pounds i believe. i just start with the center bolts, alternate sides and work toward the outer bolts. i don't think Ford specifies a sequence.

 

[bonz1234]

Thanks for all the info really appreciate it