I have a 05 coupe 5AT with a kenitx manifold, injen intake and a acessport that's tuned to the
Car. A few months ago my car started to sputter when it was at a stop and just idling. It has progressively gotten worse to the point I'm At now. When I am idling my car starts to idle super low (500-600) ,to the point it wants to die. As soon as I give it gas it responds but when I let off it acts like it just wants to die again. The accesport diagnostics gave me 4 codes...
U1001 CAN Communication Circuit
P1574 ASCD_VHL_SPD_SEN
P0171 Fuel System Lean Bank 1
P1271 A/F-Sensor 1- (B1)

Any help will be greatly appreciated.

 

Have you tried the idle air reset? Not sure when dealing with other manifolds bud.

 

I have not. I honestly don't even know how it's done.

 

I can't comment on the codes but I would make sure the MAF sensor and the inside of the throttle body are clean. And don't move the butterfly in the TB with the battery connected!!!

 

http://motordyneengineering.com/manual.pdf

Follow the last page of the document to perform idle air reset procedure. Then clean the MAF with some MAF CLEANER (ONLY) and then clean out the TB... although I would not recommend touching it.

 

With the battery disconnected, its safe to mess with the TB. Provided someone isn't man-handling it.

 

I did take the MAF out and from a visual inspection it looks to be in great shape. I also disconnected the TB and took it off and clean it up and the problem is still there. I do recall one night it was raining super hard and I was on the interstate and everytime I got in the gas it acted like it wanted to die. Assuming I was sucking up water from the cold air intake I pulled over and waited it out. Could that have shorted a sensor?

 

I have no experience with those codes but I would say try cleaning your MAF with some CRC MAF sensor cleaner then head to cleaning your TB. After all that do an Idle Air reset and you should be good. I was having the same problem and after I did all those I no longer had problems involving rpm, you'd be surprised what build up can do to your TB..

 

I cleaned the tb already and it really wasn't that bad either. I didn't clean the MAF with anything though. I just did a visual inspection on it and it looked pretty new itself. I'm going tonight to do get this cleaner for the MAF and try it out and then do the idle air reset. I'll give an update after I finish! I hope I'm lucky and it's just that.

 

Just got off work and was about to perform all the above we talked about. So I scanned the codes once more and this time I got P0302 / misfire cyl #2.

 

I had recently had sputter issues with my G too recently. Same like u when i go it runs fine when i came to a red light it would sputter like it wanted to die. Went to autozone pulled the codes and had like 6 codes. Misfire was one of them . So we pulled out the spark plugs the 6th 1 had a crack in the white part. Replaced them all now the car runs like a beaut again. No more sputter. Not sure if your cause of problem is the same is mine tho good luck man

 

Check your spark plug and ignition coil, swap from another cyl. So you know if one of those resolve the problem