Fitness Stain

My car was down due to a fuel leak. I changed the FPD with a banjo bolt, sent the injectors to RC engineering, and re-did all the fuel hose. I did a complete vaccum hose job eliminating all the emissions junk. I also did the TB mod.
Now the car starts, but the idle is like at 4000k or more...not less.
Just curious if anyone has had similar problems or not.
We suspect its an intake leak, but im not sure. Any ideas would be great.

niner

if its up to 4000 rpms i would check for the throttle plate sticking somehow before intake leaks. make sure the throttle opens and closes smoothly w/ no restrictions. after I did TB mod on one car, some of the linkage was rubbing the wrong way, and I had to grind some of it down.

Fitness Stain

BUMP

Suds7

Did you mess with the throttle cable where the 2 nuts are (where the throttle cable shielding ends). I had a problem with that after I ported mine

rotorbrain

dont forget to tell them about the LIM-to-block flange bolt that is missing.

paul

Jimmy325i

intake leaks don't cause high idles. unless your engine runs so rich it bogs at idle....

Fitness Stain

bump again in the night

rotorbrain

yes. . . yes they do. dont give out false info. ive had (on my 3rd gen) an intake leak at the TB elbow/TB. the rubber o-ring slipped out. . . luckily i got to it before it made its happy little way past the primary TB blade. anyways, i could feel the leak and the idle wouldnt go below 4-4.5k rpms. it did exactly what his car is doing. you must remember that the car doesnt measure the air if it enters or leaves past the AFM.

it could be the linkage. . . i never got a REAL chance to look at it after reading some pms. . . it could be the fact that the TB gaskets were old and dried out from tons of brake & carb cleaner sprayed on them. . . it could be the TB o-ring that just happens to be old and FLAT. . . it could be the TID that is almost like hard plastic now (i noticed that the BOV doesnt have a good seal anymore). . . it could be the LIM/block mounting bolt that is missing (those things have a certain torque patter that should be taken and if one is missing then it is definately 1) not sealing correctly in that area and 2) placing stress on the other mounting areas).

those are a lot of variables that can add up the same thing. some may not be real, but are equally as haunting and should be taken car of.

there are things called commons and variables. commons stay the same. variables are ever changing. when solving any problem that includes commons and variables which one do you think has to have the most attention?. . . thats right. . . the variables. . . they arent "true". those above mentioned problems are variables. the main goal is an engine that runs correctly. with those variables the engine cannot run to ITS potential.

gaskets are made to crush. . . thats how they seal. . . if they no longer crush, they no longer seal (correctly). you can take a chance, but you gamble. i dont know about you guys, but i cant stand going into an area that i was just in when i could have fixed it before.

done that before, dont wanna do it again. . .

paul

Fitness Stain

hehe....
look at ya....school 'in folks

Fitness Stain

another bump bites the dust

Fitness Stain

bump....anyone else have any ideas?

wankelhead

i would also say recheck all the vacum conections-i had a high idle after messing around with the intake manifold,but not as high as urs,and it was a major vacum leak.or something mechanical keeping the throttle plates open.how'bout if the [i forget what its called throttle stop pod] has come loose and is holding the thottle open.good luck
~d

Jimmy325i

Originally posted by Jimmy325i
intake leaks don't cause high idles. unless your engine runs so rich it bogs at idle....
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yes. . . yes they do. dont give out false info. ive had (on my 3rd gen) an intake leak at the TB elbow/TB. the rubber o-ring slipped out. . . luckily i got to it before it made its happy little way past the primary TB blade. anyways, i could feel the leak and the idle wouldnt go below 4-4.5k rpms. it did exactly what his car is doing. you must remember that the car doesnt measure the air if it enters or leaves past the AFM. [/quote]


So please tell me how I am wrong? The air entering the system is coming from outside the afm and therefore not being metered and accomodated for by the ecu causing a LEAN condition that will result in a lower idle unless your computer decides to compensate for the lean condition (which it very well might but rather unlikely does) and add more fuel causing a high idle. My experience with a 2nd gen car (funny,the sign did say 2nd gen at the door) having a couple vacuum leaks led to a very low idle and one that was also quite rough.

An o-ring lodged in your primary throttle plates would cause the high idle as the air couldn't be cut off, thus allowing the same situation as occurs when you hit the gas peddal. You probably had enough air volume due to the high revs to make the leaning out from unmetered air less significant.

Intake leaks cause low idles. Plain and simple! Why do you think we use combustable gases to find them? The air is getting in but not enough fuel... add fuel to the leak and the rpm climbs. voila there's the leak....

Do the same thing to an engine thats got a solid a/f ratio at idle and you'll actually bog it from adding too much fuel.