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Discussion Starter · #1 ·
So I dropped off my car at the body shop to have my bumpers painted. When I picked the car up 2 weeks later, the car ran well for the first 5 minutes. After those 5 minutes though, the car ran horribly.

The car doesn't accelerate past 2500rpm, and if you try to add more throttle the car shakes violently. BUT, there is no check engine light.

If you restart the car, the car runs fine for the first 5 minutes again. But, it always goes back to the same problem.

This is where the problem gets weird. Once the car starts to run poorly, I can put the car in park and rev the car to redline with no problem.

_________________


What causes this problem?

Has anyone ever had this problem before? If so, how did you diagnose and fix it?

Thanks,
Danny
 

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Body shop to blame? Should try to talk to the shop to see if any of their employee had taken the vehicle out for a spin.

What's your turbo setup and what kind of ecu are you running?
 

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since theres no check engine light...its ahrd to say because pretty much any sensor will turn on the light...but there are a few sensors that wont elt you go over a certain revolution speed

if i were you id take a good look under the hood and just see if anyhting look out of the ordinary.....

honestly unless someone else ahd the same problem idk if anyone will be able to pin point the problem on here
 

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1) look for a loose hose, you might have a vacuum leak that when revving the car it would close the leak but than under load the leak is present.
2) look over the engine bay, look for loose clamps around the intake or even a loose IC connector.
 

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Again it sounds like a loose line...check all hoses and what not
 

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if yuo have a boost guage watch it as you rev up...if u cant pass 2500 even while just cruising to that speed then its nothing to do with the ic piping...

also if its a vacume leak..at idle your car will sputter and run rough...even if tis small itll still be noticeable

like previously mentioned..take it back to the body shop and let them know what happened..make sure if an idiot was messing with it he gets delt with
 

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Discussion Starter · #7 ·
I wish this was a simple problem to fix, but I'm sorry to say that none of you guys are right. It is not a boost leak, it is not a loose fitting, or any of the above.

For the first 5 minutes you can drive the car fine, hit 15psi, no problem.

FOR ANYONE THAT HAS A BACKGROUND IN ELECTRONICS, ETC..

The car is running in open loop upon start-up for the first 5 minutes. It then for some reason goes into closed loop. This is why the car starts to run poorly. I want to know why it does this, what could possibly cause this, and how it can be fixed.

Eminence: I am running a greddy e-manage on a Turbo East Turbo Kit. The car has given me no problems for 3 years boosted.

I have tracked the problem down to either a fuel, ignition/spark, or electrical/ecu issue. It is NOT a mechanical problem.

Any more comments or feedback are greatly appreciated.
 

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danny, is there a reset on the emanage? liek a built in safety? i had a similar issue with my aem, and it kept going to a default mode. i had to reset some settings and i was fine. it was almost like it wa sin lymph mode after i drover for a few minutes.

maybe for some reason they had your battery disconnected(alarm going off or some shit) and the emanage had no power and reset itself to some default? im not too familiar with emanage. talk to rich about it. get a laptop on that thing.
 

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ughh;

Seems like im going to be doing my cars bodyWork/paint My damself
=/
 

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^or just take your keys. or disconnect your fuel pump. or go somewhere you trust. haha
 

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thats sounds like a leak from the FPR, i encountered this before with no CEL's.

check the lines behind your intake manifold, the block on top of the runners.
 

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To rule out an open or closed loop problem, plug an OBD2 scanner and have someone drive your car while you monitor the fuel trims. Look for a pattern where the fuel trim looks weird when you're seeing this drivability problem and compare it to the fuel trims when it's driving smoothly. Honestly something like this is hard to figure out over the web, you're going to have to do a lot of debugging to see if there's something that looks weird. The only other thing I would suggest is plugging a laptop in and log the sensors via the Emanage software and compare them as well. That's the only real way to find the problem.
 

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What about a bad MAF Sensor? Causing limp mode?
 

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ohh yeah I see that
 

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Unplug the front O2 sensor. See if it runs better after the 5 mins or whatever. If it runs better, that confirms that when the system goes into close loop it is either removing or adding to much fuel.

Try reloading your Emanage map.

This will trip the CEL though.
 
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