So I just pulled my intake manifold, expecting to find a couple of shot Comp R lifters. NOT the case. All of them are fine. No broken locks, no collapsed lifters, NADA. I can't even compress them by hand.

Note what I last said. I can't compress them by hand. This is after sitting for three weeks. When the car was last run with it's problems, there were a couple that were just spongy while I was adjusting them hot. So......

Could, or rather is it possible, that as a lifter is brought alive from a cold start, that as it "pumps up" it's performance degrades??? Could that be my problem??

 

Forgive me... but what exactly is the problem thats leading you to test lifter integrity? You getting valve float at unusual rpm or something?

 

Let me direct you here.

Cliff Notes:

I'm getting a load up on fuel for some reason. L&STerms going full rich, car sputters, ANY kind of fast throttle movement causes a cut-out which at times will kill the car. Fuel load up was verified on the dyno wide band. O2 sensors going into the 700+ range and staying.

Opti, Plugs, Wires, Coil, ICM, Fuel Pump, AFPR, Fuel Filter, MAP Sensor, O2, and shortblock were all replaced with no luck. All other sensors reading fine with no gaps or holes in the readings, via datamaster.

I've got the opti off because of a DTC 36 (High Res Failure) after the new shortblock, and figured I'd pull the manifold to check the lifters because I was having a helluva time getting my lash set for some reason. Last time I tried to set the lash, the car was warm, and I had a couple of VERY spongy lifters, they were extremely easy to compress by hand with the pushrod. Now, I can't budge them. I'm also converting to heated O2's. So, back to the original bolded question in the top post.

 

Grr... I see... well then. Back to your original question.

As far as lifters go, the only possible mechanical reasoning behind bad perf. at warm temps would be wear. As the oil thin it causes the lifters to bleed off at a faster rate. Other than that, weak springs are all I can think of... Wish I could help you out more than that because Im sure its crossed your mind already.

 

Yeah, not going to be the valve springs. They're XE618 springs from Combo. 150# on the seat and 350# when compressed @ .550 when installed @ 1.8". They've got less than 30 miles on them so far, along with about an hours worth of run time at idle.

Looks like I may be sending the fuel injectors out. Anyone ever hear of a SVO 30# injector crapping out with less than 1K miles?

 

cant say i have...

 

Well, I talked to Comp just a little while ago, and they'd never heard of a lifter losing it's performance as the motor heated up, but weren't closed to the possibility of it. I got told to go ahead and give the stockers I picked up a shot, and if they work out to call them back and send in the Comp R's under warranty.

So.....think the stockers will hold up to 150# on the seat and 350# @ .600 lift????

 

Stocker's should work fine,but probably won't cure your "rich" problem.Sounds like a tuning issue.

 

Most definitely not a tuning issue. There's been 5 revised tunes in the car on the new setup, and over 10 on the old setup, with the same results from both.

 

I don't think it is mechanical.IAS motor maybe?

 

Shouldn't be. It's got a brand new <50 mile shortblock.

I forgot to post this from my phone call with comp:
The Comp R lifters should not bleed down after sitting. I did a double check and got the same answer. They hold oil better than stockers.

 

I have a comp R that complains continually, but no power or driveability have been effected.

I pulled the whole valvetrain and double checked it all and it all looks perfect, springs are fine (K-motion K-800s) cam has hardly any wear, and the lifters still look new except for shiny wear spots from the lifter bores.

But I still have this nice continual valvetrain tap.

 

Idle air motor has nothing to do with the lifter's but will make it run rich down low.

 

My IAC is fine. I've got it set and it's fine every time I look at the scanner.

 

My car ran similar when it had too much lash.