Another KA Idle Issue

[LeandroS14]

Ive been having some issues with my idle

the cars idling good but it is hiccuping, every couple seconds it drops the rpms then goes back to normal. Seems like a misfire or something

Ive been working with a local shop that specializes in 240s to figure it out but we haven't pinpointed it just yet.

We noticed my group strap was missing, so I added another one from motor to body and for the next 3 drives the idle was perfect and the problem was fixed. now it came back again!

Any ideas on what it could be?

[240sxfan6882]

Ive been having some issues with my idle

the cars idling good but it is hiccuping, every couple seconds it drops the rpms then goes back to normal. Seems like a misfire or something

Ive been working with a local shop that specializes in 240s to figure it out but we haven't pinpointed it just yet.

We noticed my group strap was missing, so I added another one from motor to body and for the next 3 drives the idle was perfect and the problem was fixed. now it came back again!

Any ideas on what it could be?

I had this problem too since my engine was swapped when it was built.

It would feel like the car idled OK when it was cold..but soon after it starts to warm up I would hear the RPMs drop and make a hiccup sound...then it would return...then do it again. I would get in the car and rev it up and hold it and it would still do it.

I checked timing, spark, vacuum leaks, injectors...all clear.

What I had was a "CODE 34 - Knock Sensor". Check for it on your ECU. It wont give you a CEL and thats why I went so long without detecting it. I took care of it..no more code...perfect idle! Try that

[LeandroS14]

Just an update, I got another knock sensor harness because mine was messed up and I connected everything, I have to go to the autoparts store today to clear the code. The idle issue seems to go away for a day or so when I disconnect the neg on the battery (resetting the ecu) but that was prior to the knock sensor. Ill update this thread again in a couple days if the issue continues

[LeandroS14]

Ok so the problem is back but this time its a little different.

The idle stays smooth and steady with the A/C OFF, but as soon as I flick the A/C ON the idle starts to stumble.

Im also throwing codes
p1400 EGR & Canister solenoid valve
p1401 EGR Temp sensor

I took out and blocked off all the EGR stuff about a year ago

Also when I first turn the car on from a cold start is it very hesitant until the engine warms up a little

[LeandroS14]

Any idea anyone?

Ive look everywhere online and tried numerous things. I even took it to a shop "Carisma" out here in orlando, fl. Its progressively getting worse

[wesamiss]

Also when I first turn the car on from a cold start is it very hesitant until the engine warms up a little

I had this exact problem. Ended up being a fuel pump on its last leg. I also replaced the IACV and air regulator, and found a vacuum leak while fixing all this stuff. After replacing all this stuff i put a little seafoam in it. She runs like a top meow.

check the FSM, great place to trouble shoot



CARisma probably has the best customer service I have ever experienced.

[LeandroS14]

Yea they were very helpful but the mechanic said he thinks its electrical and he doesnt think itll be worth my money to get done by him because it would prob take him too many hours.

I dont believe that its a wiring issue

Did you have the issue only when the A/C was on?

[LeandroS14]

anyone? anything helps!

Also I noticed its doing the issue more after the car warms up, at least thats what its doing now

[Freise]

Have you looked at the IACV AAV stuff at all? If it's related to the A/C being on/off, I would look here.

[LeandroS14]

Yea Ive checked it out but now it does it when the idle is off, I still havent figured it out