96 SOHC Accent: Still Idling High and I have no idea why :)

[captain.navarre]

Hi one and all,

This is my last ditch hope to find and answer before toss the Idle Speed Actuator and set the revs via the Throttle Body.

So, the car is a SOHC X3 Accent. The car was idling high before I changed the following but is still idling high.

The standard TB has been changed over to Elantra TB. The MAF from the Elantra was installed, but in order for the car to run without sounding like a rotary and tossing black smoke out the back, I replaced the Elantra sensor with the standard Accent sensor and tossed in a new set of Elantra injectors.

The plastic manifold (typically Australian) has been replaced with an Alloy two piece, thanks again to Skierd for this one!! All the lines from the manifold have been either checked or replaced to ensure that a vacuum leak is not the problem.

The idle is anywhere between 1500 to 2000. I have reset the ecu and taken it for a drive. While at the lights and idling at 2000, I let the clutch out to bring down the revs to 1000 then put the clutch in, and it stayed at 1000 rpm, but would not do it the next time I tried and hasn't worked subsequently.

The idle speed actuator has been replaced. While the engine is running, and idling at 2000 rpm or so, I pull the connector off the Idle Speed Actuator and the revs drop down nicely to about 1000rpm, then I plug it back in, and up she goes to 2000rpm.

The TB is fully closed at idle and nothing is binding up or sticking.

On the up side, the difference the Elantra/Tib TB and injectors has made is remarkable.

I have an eManage sitting here awaiting the turbo installation and wonder is there any benifit if I put in on the car now??

Any suggestions or information would be much appreciated, as I have checked and tried just about everything to get the idle down.

Safe driving

[incubus_boader]

hmm... i replaced my throttle body on my accent with one from a 240sx...when i first started it it idled high like yours...the problem was i didnt plumb the IAC valve back into the intake system. it must be plumbed in behind the MAF or it will pull in air unaccounted for by the maf and cause a high and fluctauting idle...When i first did it i lef t the IAC open to the atmospehere and my car acted teh same way. plumped it in and now it runs good as stock! hope this helps

[captain.navarre]

Hi Incubus

Thanks for the comments, the Idle Speed Actuator is plumbed as original with it conneted to custom silicon piping between the MAF and TB.

[incubus_boader]

hmm im stumoed...when you replaced the intake manifold what did you use for a gasket? I know this isnt that helpful and likly you already tried this but, use rtv sealent between the head and lower intake manifold, upper and lower intake manifold and betwwen the upper intake manifold and TB.

[captain.navarre]

Yeah, mate, she's all sealed. Done the soapy water bizzo and all. It idle high with the other manifold after I removed the ISA hose (while the engine was off). I just wanted to check something and I reconnected the hose and she's idled high ever since. I was hoping that I might catch whatever the problem was in the manifold, IAS, etc changeover.

I've just let the car idle for about 10 minutes and the revs have slowly come back to 1000rpm, so I guess the ISA is working. But as soon as you give it throttle, it then goes back to 2000rpm. What I find interesting is that if I pull the electrical plug out of the ISA, it idles perfectly. So I would have thought, that with a fully closed TB, and no ISA, for sure the car would stall, but it doesn't which is why a vacuum leak appears to be the issue, but I swear on my lefty, I have doubled checked all possible areas for a leak.

Maybe I should go the way of omgbossis21, and just block off the ISA (still keep in connected electrically) and set idle using the TB stop screw.

Thanks for the comments, and keep em' coming

[mfoote]

i didnt bother to read the other posts but did u loosen the throttle cable a bit,

[greg442]

It sounds like you’re in cold engine high speed idle mode. Did your engine temp sensor go bad during all this part swapping?

[ASperilla]

Disconect your idel valve then let me know

[X3Jason]

all wrong...

are you running beta injectors and beta maf? either run both or neither, stick w/ the x3 injectors and x3 maf. if you run beta maf and accent injectors your ecu can't figure out wtf is up and can't make a match.

+5 points for me :clap: