Alright, so I've been reading tons of posts on cold starts and such, trying to figure out my issue. One post recommended looking at the battery, so that's where I went. Could this be the cause of my cold start issues and lean fuel condition? I'm searching for help and can't figure it out. What should I do to fix this? Clean it off or new battery or ?



So far I've changed/replaced:
MAF
Re-oiled K&N Filter
Spark Plugs
Cleaned MAF w/ MAF cleaner
Changed both O2 sensors
Changed Fuel Filter

Only code i'm pulling is P1128 Long Term Fuel Trim mult.,Bank1 System too Lean

Any help, again, would be appreciated....

 

If its not the filter or the o2, then you most likely have a vac leak. The vac line to the fpr (fuel pressure regulator) is a problem spot and would mess with fuelling. Also i wold clear the code if you havent since you could of fixed it already and it just hasnt gone away yet

 

i had cold start issues and thought it might be the battery - turns out, I had a huge leak in the hose on top of the DV where the fitting tightens. it was worn right through! I also think my MAF was bad, so I replaced it with one that I thought was bad that I had swapped out 6 months ago... turns out - the old one wasnt bad, but the newer one was...

 

We've cleared codes after every set of "repairs". Had a couple other random codes, but the one that keeps coming back is the P1128. Hopefully the weather will cooperate and I can look at the those spots you're suggesting - would a vac leak register on my boost gauge? Aside from when it first starts up (and settles at 10hg), it primarily idles at 20-21hg. From this I assumed that there wasn't a vac leak, but I wouldn't be suprised to hear otherwise.

 

as far as a battery, optima makes the best **** out there. Yes they are expensive, but customer service and product warranty can't be beaten. I hit a dodge dually with my BT corrado and cracked the case. It was replaced for free. Not to mention, you can mount it any way you want (even upside down). As far as a way to diagnose your problem, take it to the dealership. Let them tell you what's wrong with it. They can't charge you for an estimate. Oh and, buy a liquid tt so you can clear your own codes.

 

I did some more looking and trying stuff, and it seems that it only idles w/ less vacuum when this line is being used (the one w/ the white filter on it):



I'm thinking this is the secondary air pump line (?). When I ran the car for a bit, then shut it off, and re-started it, this line didn't seem to be doing anything and the car idle'd straight to 20hg. I THOUGHT I felt a small random burst of air around that line when the car was running, but couldn't re-find it (so I'm not sure if it actually was leaking from that line). I'm thinking there's something wrong in my secondary air pump system that could be causing this.

Next question, is this the combination valve for that system?



It sits in the same area of the MAF, air filter, and the line pictured above (it's to the upper left of the white filter in first picture)[all to the drivers side of the engine].

 

That white filter is the intake for the secondary air injection, that second pic is the other half of the system, turning to a steel line and running back to the exhaust.

A slightly lower reading is normal on cold start (17-18ish), and once warmed up, 20-22in-hg is normal.

I really have no clue what the cause of the cold start thing is, I've been dealing with it for years now, my 180, and now my 225. All sorts of parts have been replaced, some things have been upgraded or modified, and nothing changes the cold start issue.

One thing I haven't heard anyone else mention, but I have, is that my car will start fine with a full tank of gas, and only starts the issue when Im around 1/4 tank or less.

What I (or anyone with the problem) need to do, is hook up a fuel pressure gauge and see if the system is coming up to proper pressure when the car is started.

 

not to threadjack but you got details on that rado?

 

haha join the club mine does it too but only sometimes. There are times where it will die or idle real low then spudder then go back up to normal or just stumble a lil bit and thats it. I would recommend only getting gas from one gas station and fill it when it gets to a half tank. That seems to have worked for me but im no audi tech. good luck.

 

Mine seems to not matter if I'm full on gas or not. I also believe I have some sort of battery issue, but not sure if the two could/would be related. This morning I went out and had to turn the key 8-10 times before it finally attempted to start. The first few times there were no sounds or nothing when I turned it. When it did start up, however, it started up and idle'd fine, even though it was cold this morning......???