Runs ruff cold

Finally

New member
Recently my 03 on start up runs like it needs a choke,it sputters and I have to step heavy to get it to rpm before it smooths out.
Once it's warm it fine,it always has had a rich smell with the MartyO tune on cold but this running rough is new.
Could the rich startup foul anything up ? My last trip into town the engine light came on with a P1152 code which apparently is a slow 02 sensor and now I fear changing them and fouling them up again.
My engine mods are,JLT CAI ,Stainless Works long tubes with cat deletes,all accounted for in the tune.

Thanks all

Tony
 
Tony, I looked and the tune file is not rich at idle or start up. So, I can safely say the tune is not what is causing the 02 to foul.

I can revise your file to give it a small rev at start up like these cars had from the factory if you want to try that. Let me know.

Out of curiosity, do you have a wideband on the car?
 
Tony, I looked and the tune file is not rich at idle or start up. So, I can safely say the tune is not what is causing the 02 to foul.

I can revise your file to give it a small rev at start up like these cars had from the factory if you want to try that. Let me know.

Out of curiosity, do you have a wideband on the car?

Hi Marty.
In my reading I found where someone said they run a little rich with a tune so that has never bothered me,I have left it to idle for 10 min on a summer day and it will still do it so I'm not sure if that adjustment will fix it,it did not run like this before the headers and cat delete so this is why I thought maybe that's why the 02's are maybe working harder with more flow going past them or something like that.
Sorry Marty I don't have a gauge but I should put one on..
 
For two years mine never stayed running on a cold start. I had to two step it for about a minute every time. It started right after a tune I received from another source who kept blaming my IAC, even my brand new Motorcraft one...

Marty and Jeff set mine to rev on start up again and all is peachy. And yes, all cars carbed or injected run a tad rich on start up, otherwise they would die. (IAC or choke)


Builder Of Badassery
 
For two years mine never stayed running on a cold start. I had to two step it for about a minute every time. It started right after a tune I received from another source who kept blaming my IAC, even my brand new Motorcraft one...

Marty and Jeff set mine to rev on start up again and all is peachy. And yes, all cars carbed or injected run a tad rich on start up, otherwise they would die. (IAC or choke)


Builder Of Badassery


Are your thoughts the same if mine does idle,?
 
Does yours have any start up rev like the factory tune had?


Builder Of Badassery


Lol I had to go out and start it to see,it fires up and drops to 900 rpm and stays there,funny thing is now the ABS and Brake light is staying on now,maybe it's got to do with the car sitting in the heat outside for a week but this also has never happened before..
 
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Almost sounds like an injector leaking by. You say it drops to 900 so I'm assuming it revs higher like I asked. But you say it's rough like loading up till you clear it out. Sounds like it's time to pull the plugs and compare to start with.

As for your brake and ABS, run a scan and check the fluid.




Builder Of Badassery
 
Almost sounds like an injector leaking by. You say it drops to 900 so I'm assuming it revs higher like I asked. But you say it's rough like loading up till you clear it out. Sounds like it's time to pull the plugs and compare to start with.

As for your brake and ABS, run a scan and check the fluid.




Builder Of Badassery

It shoots too about 1500 and immediately drops to 900 rpm,we have some hot weather right now so it didn't run bad on startup this time..
 
So I gave it the once over and all is snug with the CAI,could this issue be that the 02's just need replacement.
I already have two new one to install, they are NTK 22500's.from what I can figure is they are the down stream.can anyone confirm this for me.

Thanks
Tony
 
Hi guys
Could any of the symptoms I described happen if a battery was going bad,I went out this morning and she was completely dead,I put my tester on it and said bad battery. .
 
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