Surging Idle

[paton]

My CL-S 6MT (J32A2) swap is running, open header, no 02 (still waiting for header to arrive) and the idle surges up and down once running. I don't have a working tach so I'm assuming it revs to about 1800 RPM or so and then plummets. Then goes back up... up and down.

I hooked up an oscilloscope to the injector of the left cylinder on the rear bank. When the idle drops, the voltage is being cut to the injector. So I'm also going to assume that all the injectors are being cut off.

I tried a different MAP, suspected the TPS so then tried another A2 throttle body, no changes.

I have blocked off any vacuum leaks, tried to block the IACV port. It does change the idle and it starts to behave differently, then dies.

I have tried unplugging the IACV and then it goes into a very fast up and down idle, but staying around 1200 RPM or so.

I think I have more issues than just the IACV but where to start...

I will take a video tomorrow and post it up so we can all have a listen and a closer look.

Any suggestions?

[junior78]

sounds like my problem what happens if you plug the iac port inside the throttle body

[tonynail]

sound like you used to have the same thing as me, i was struggle to figure out my problem, gave up and until i hook everything up include my alternator belt and it stop. still no problem a year later. make sure you somehow got the water into the iacv. for me i raise the radiator up above the iacv and let run till the water pump and put the radiator back in place. iacv for the j is the same as the k.

[tonynail]

the biggest problem with the j swap is because the radiator sit too low, and fluid can't get to the port for the tb and iacv to be properly working all the time. that is my opinion.

[paton]

sound like you used to have the same thing as me, i was struggle to figure out my problem, gave up and until i hook everything up include my alternator belt and it stop. still no problem a year later. make sure you somehow got the water into the iacv. for me i raise the radiator up above the iacv and let run till the water pump and put the radiator back in place. iacv for the j is the same as the k.

That's interesting. I don't have a belt for the alternator yet, and this is starting to make sense. When you say the IACV is the same for the J as it is for the K, are you trying to reference a problem that the K's have as well? Or just for comparison sake?

[paton]

OK I have the alternator belt on and it is now charging. It did NOT change the idle issue.

I wasn't able to use my code scanner because I wasn't getting 12V at the scanner port, but then I applied 12V with a back probe and it worked. I have the following codes:

P1607 - Immobilizer removed (PCM Internal Circuit Failure)
P1298 - Electrical Load Detector
P0135 - Primary O2 Heater
P0141 - Secondary O2 Heater
P0560 - PCM Backup Circuit Low Voltage

Could these be related to my surging idle?

[LKSi]

My problem was solved by putting the car on the ground haha. I guess coolant wasn't reaching the iacv as previously stated or something to that effect.

[tonynail]

OK I have the alternator belt on and it is now charging. It did NOT change the idle issue.

I wasn't able to use my code scanner because I wasn't getting 12V at the scanner port, but then I applied 12V with a back probe and it worked. I have the following codes:

P1607 - Immobilizer removed (PCM Internal Circuit Failure)
P1298 - Electrical Load Detector
P0135 - Primary O2 Heater
P0141 - Secondary O2 Heater
P0560 - PCM Backup Circuit Low Voltage

Could these be related to my surging idle?

maybe, you must fix the eld and po2 first, let it run. if it still does it take it off and check to see if there is fluid inside of the iacv. if there is not much fluid figure way to get fluid into it. if there is than go back to electrical. assume you iacv is good.

[paton]

When I plug the lower port in the IACV, it turns into a nice calm idle. But what does this mean?

I do NOT have coolant in the IACV, I haven't managed to bleed all the air out of the system, and so far only have about 3 litres of coolant in the engine.

[junior78]

When I plug the lower port in the IACV, it turns into a nice calm idle. But what does this mean?

I do NOT have coolant in the IACV, I haven't managed to bleed all the air out of the system, and so far only have about 3 litres of coolant in the engine.

that could be your problem because i was surging but after i burped the air out of my system my car was ok but one thing i did to help bleed the system i jacked the front of the car up just because the j series motors the head sits higher than the rad you could try this before you buy an iacv

[paton]

Got coolant to the IACV, no change. I blocked the lower port with some metal tape, but left the pipe over top of the throttle body open to atmosphere. It idles great, but drives like crap. Though I have not checked to see what codes I am throwing since I did all this, I'm not sure what I'll do next. Tomorrow is a new day.

When I took it out for a drive, I was getting on the throttle lightly and it would go go go... and then cut out, rev down down down, then go go go suddenly, like a burst of power. It's hard to describe, and the only instruments I have connected are my coolant temp, oil pressure and engine light so it's difficult to tell what's up without an RPM or speed reference.

I had symptoms like this with a B series and it was a MAP issue. Going to pull the codes tomorrow and go from there.

[drocha86]

those codes are normal your not running the eld with that swap its not going to read it on the j series ecu its ok..the o2 sensors are no biggie just hook them up...and internal cicuit failure is normal is the ecu from an automatic or is it jumped to kick vtec without the speed sensor there multiple factors on that code. and the surging change your air idle control valve there a lilttle pricey

[RPM SYSTEMS]

if your car not running right , then how are you give out info how to make the wiring harness? and YES i type like a little kid, but my car runs LOL!!!!

p.s. i am a lying peice of poop too!!!!