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New Injectors on TLAO Surging Idle?

If you are getting ping on 93 octane I would expect something to be off on your setup, base timing or something like that. on 91octane I can get 14psi without knock on nearly the same setup. Was there knock with the old injectors? When did the knock start?

No no... I don't get ANY ping once it learns. It's only while it's learning the boost curve and it's only in the lower RPMs. Once the ECU learns though, no knock.

So far this is the same with old injectors and AMM and these injectors and new AMM... the only difference is the surging idle.

That said, it's shifted from a revving (akin to when there's a huge vac leak) to more of holding 1600rpm and then cutting the (something) out to drop the idle but it almost stalls and wakes itself back up to 1600rpm. When I got to work this morning and it reached the idle (800rpm) consistently, I sat there for about ten minutes and the AFRs were hunting around while the RPM was changing (only perceptible by ear not gauge) +- a few RPM.

AFAIK my timing should be straight up and down... my head does have a bunch of metal removed from it though... not sure if that affects the timing...?
 
No clue, LH is odd and when mixing and matching parts you can get odd issues. Plus we are all using used AMMs.

Let it learn and see how it goes but always be aware of possible issues.
 
No clue, LH is odd and when mixing and matching parts you can get odd issues. Plus we are all using used AMMs.

Let it learn and see how it goes but always be aware of possible issues.

Yeah no doubt... I;m always curious to how the inner workings of a million year old computer works lol. I'm not trying to disregard your suggestions, they're well pointed. I'm going to follow the flow chart for right now and see if it learns properly. If I can't get to where I need to... then I'll begin looking around with the sprays and the smoke and such.
 
So... If I unplug my iac. It idles fine. 2 questions...
1. Where does this device ground? Is it by chance one of these possibly stressed wires on the fuel rail?
2. Should I do exactly what I've said I'd do and "trust the system", or unplug the gd thing? (I'm leaning towards cleaning tbh, but... Also how can I test it's effectiveness?)
 
I ran my 744 without an iac and it ran fine for years. My current 945 still has everything with the 65lb and 012 and it runs fine also. So whatever you want to do just make sure the basics are working ha.
 
So today I yanked the IACV and cleaned it thoroughly and then lubed it all up. Plugged it all back in and the idle is still garbage. If I pinch the hose connected to the IAC and pre-TB I can get the idle to come down.

I pulled the connector for the IACV and it threw a CEL obv, but the idle was much more reasonable... maybe about 1100 and consistent. The AFRs though swayed a lot between 13 and 15 while just idling in a pretty consistent game of chase/tag.

I propane tested for vac leaks as well as a BLT and both were negative. I didn't have time to check with smoke.

I'm getting no codes with everything connected properly. What other options do I have here? O2 sensor is about a year old...

Knock sensor? ECT sensor? Would these throw codes in LH 2.4? Wouldn't they have manifested themselves in my 007 and orange tops setup?
 
Also... does anybody know what the screw (I assume adjustment) ON the IACV does? Mine is like... hot glued over but if this adjusts something useful... now is a great time to know.
 
Ok squad. I went through everything this weekend. What I found was that my car was unable to run if I pinched the iac hose shut. This led me to the throttle plate idle specs and I found that this was eeeeevvver so slightly out. Adjusted this with the felt gauge. Started it up and...

Same problem.

I decided to try my old amm but in my haste, I hooked up my 2.2 amm aaaaand... Same thing. Surprised the car ran though.

After all of this, I ended up here... prior to adjusting my throttle plate, the car would not run with the iac hose pinched completely closed. At all. Post adjustment, it idles fine with the hose pinched off completely. WARMED UP. At cold it's about 500rpm... needs a little nudge to wake itself up.

The iac tested within spec (resistance) and actuated with voltage. I didn't feel it vibrating when the engine was running but like, trying to feel something vibrate on a red block is impossible. Everything vibrates.

Where does this leave me? Is my iac functional but too slow?
 
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LH 24 has a test function that allows you to check (hear) the injectors clicking, the iac clicking, and the cold start injector (if equipped). I'd run that test and make sure everything is clicking as it should be.
 
LH 24 has a test function that allows you to check (hear) the injectors clicking, the iac clicking, and the cold start injector (if equipped). I'd run that test and make sure everything is clicking as it should be.

I did and it did/was. The thing is... this really presents as a vac leak and despite the IACV testing completely fine, I STILL suspect it. Just because the resistance and voltage are all good doesn't mean it's o-ring hasn't blown itself up???

Otherwise I'm at a loss. I know I'm still in the early "learning" phase... but with the weather warmed up, sitting in stop and go and revving to 2k+ RPM every 2 seconds is taxing my cooling system. And I'm on the 3 row with tropical fan...

Anyway... flushed/cleaned the coolant this weekend as well.

I'm still open to other suggestions while I drive around with the car revving.
 
If the idle is hunting from 1-2k rpm when stopped you have a leak and need to pressure test. That or maybe something like the TPS isn't set right. If when the iac is blocked the issue goes away it sure sounds like something like the iac or iac hose is at fault.
 
If the idle is hunting from 1-2k rpm when stopped you have a leak and need to pressure test. That or maybe something like the TPS isn't set right. If when the iac is blocked the issue goes away it sure sounds like something like the iac or iac hose is at fault.

Haha... I just sent you a PM.

Yeah man... something is up. I've got a new IACV heading in tomorrow so we'll see if that settles it.

It passed the BLT with no issues. Even with soapy water BUT... I suppose I could just BLT the IACV itself which I did NOT do... hmmm.
 
It's a split hose on the manifold side of the iacv. Of course it was this. I have no idea why I ever would've thought it WASN'T this. But... That hose is like the most impossible one to replicate with auto store parts. But... It's fixed. I'm an idiot.
 
Well... good news. FCP shipped me the wrong parts so I made a hose up out of some PEX 90 degree elbows and vac hose.

The revving is back but this time it's more of a high idle (~1600rpm) and then it chops out, saves itself and comes back up.

I reset the ECU again and my AFRs are like 11s? WTH is going on man????
 
On a reset ECU expect idle and cruise afr's to be rich for the first or second start, once you get one full cold start cycle in it afr's should be correct.

Sure sound like you have a vac leak which will cause a ton of issues.
 
On a reset ECU expect idle and cruise afr's to be rich for the first or second start, once you get one full cold start cycle in it afr's should be correct.

Sure sound like you have a vac leak which will cause a ton of issues.

Yeah I'm working on it. It's not the vac leak style revving so it might be just the ECU squaring up.

Oddly I had unplugged an injector to get my iacv hose into position on the intake manifold. I forgot about it and started it up and it's idle was perfect. Aside from the miss which I thought was just my cam. Anyway. Plugged it in. Reset. Back to high idle.
 
This is coming and going now which is leading me to believe it's more LH trying to sort things out than a vac leak... but that's me being optimistic.

Anybody want to grace me with new vac leak methods? When I did the smoke and also the propane I wasn't able to find anything...
 
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