Code P1128! Possible cause of my startup issues?!?!?

[mark001]

I'm getting code P1128 (Long Term Fuel Trim mult.,Bank1 System too Lean)
First of all, the car is a stage 3

Well, I've been having start up issues for a while now. It basically started one morning when I tried to fire the car up and it took me about a minute to do so. It seems as time goes by/ the colder it gets that it takes more and more to start it up.
-I checked the ignition first. I got a little shock on all 6 coils so I'm assuming that ignition works properly...
-Next was the fuel filter which I changed. No change
-Then, I switched to a new fuel pump. No dice
-I switched the green coolant sensor as someone mentioned that it might be the issue but once again, no change.

Now I'm getting frustrated (it sucks when people are staring at you, wondering why an expensive looking luxury car is having issues) and don't know wtf is going on or if code P1128 (Long Term Fuel Trim mult.,Bank1 System too Lean) has anything to do with my startup issues. I only experience these issues on cold start ups. When I crank it for about 1-2 mins on cold starts I start smelling fuel. But once the car is warmed up it will start right away with the turn of the key. No gasoline smell these times.

What else could be the issue?!?? I'm pretty sure I replaced everything that was said could be causing the issue but nothing has worked. WTF?!

[_hmnib5]

did u check the egr?

[mark001]

egr?

[_hmnib5]

egr valve. it help regulate your fuel flow.
Mine is kinda on its way out and I sometimes have trouble starting the car.
just a thought

[megafreakindeth]

egr valve. it help regulate your fuel flow.

does not


the error code means you have an air leak. check the bypass valves and check valves. and make sure there arent any broken vac hoses anywhere. this would also make it hard to start.

[mark001]

I'm kind of confused when you say "bypass valves and check valves" Are you refering to the n249?

[mark001]

does not


the error code means you have an air leak. check the bypass valves and check valves. and make sure there arent any broken vac hoses anywhere. this would also make it hard to start.

also, if it was a vac leak wouldn't it be difficult to start the car up everytime and not only when the engine is cold?

[NefMoto]

My guess is you have a bad O2 sensor on bank 1. Anything else I can think of would cause you to run rich, or cause a problem on both banks.

[kylel2838]

Generally a system too lean code is caused by a vacuum leak or leaking intake manifold gaskets. Extra air being introduced into the engine by said leak post MAF and the MAF isn't adjusting the fuel mixture up to compensate, thus throwing a lean code. I believe that the lean code is triggered by the O2 sensor readings in cases like this, but in most cases that I have found it is usually a vacuum leak that is the culprit.

[NefMoto]

Generally a system too lean code is caused by a vacuum leak or leaking intake manifold gaskets. Extra air being introduced into the engine by said leak post MAF and the MAF isn't adjusting the fuel mixture up to compensate, thus throwing a lean code. I believe that the lean code is triggered by the O2 sensor readings in cases like this, but in most cases that I have found it is usually a vacuum leak that is the culprit.

You should get the same error code on both banks if this is the case.

Make sure you don't have any small leaks from the fuel injectors not seating properly.

[mark001]

I'll have to do a leak test. All the vac lines seem in tact so I'm not sure where the leak (if it's a leak in fact) is coming from. I still don't understand how a leak could cause startup issues ONLY on cold startups.

[ski&drive]

do you have a boost gauge?

that will tell you if the vacuum is too low

[kylel2838]

I'll have to do a leak test. All the vac lines seem in tact so I'm not sure where the leak (if it's a leak in fact) is coming from. I still don't understand how a leak could cause startup issues ONLY on cold startups.

I have seen many V12 Jaguar XJS's that have a cracked vacuum lines leading to one of the fuel pressure regulators cause cold start only issues. I know it is a Bosch FI system on the V12's, but it may be something to start at?

[Vwdude]

Does the car have a Mass Air Flow sensor? that could be the problem. I had the same problem with my VW.

[ski&drive]

Does the car have a Mass Air Flow sensor?

Nice question

[mark001]

of course it has a maf sensor.

I'll do a fuel pressure test once my tester arrives and I pick it up. I checked ignition already and it's good. Here's what I did/replace so far in order to TRY and get rid of this issue:

-Replaced coolant sensor
-Fuel filter
-Fuel Pressure regulator
-Fuel pump
-Coilpacks (ignition is good)
-Spark plugs

Fuel wise...what else could be contributing to fuel pressure loss besides injectors?

[^@ViVid]

Like I said in you're first thread dude.

So you are using the correct size battery for a 6 cyclinder right? If you are using say a smaller batter for a 4cyclinder it will take more cranks to start the car. Check the vacuum line to the MAP sensor and make sure the MAP sensor holds vacuum (need a vacuum pump).

With engine off, apply vacuum to the EGR valve. It should hold vacuum. Apply 20 inHG and then start the engine, the vacuum should drop to zero. ?

[mark001]

EGR valve as in Exhaust Gas Recirculation Valve? Where exactly is it located on these cars?

[Zba]

How many miles do you have? It's possible that you have excessive carbon buildup on the valves, which causes to valves to hang open and then the lifters bleed down. Does the car start easier/only when you open the throttle all the way?

[mark001]

I looked through my throttle body today as I was inspecting the tbb for tears and noticed a small puddle of oil inside the intake manifold....wtf is this supposed to mean? That's not normal, is it?

[a4turbo_2002]

Does anyone ever actually figure out there lean conditions lol

[Zackb5audacious]

I'm having these same issues p1128 p1130 p1136 p1138 my o2s are deleted out I know my valve gasket is bad not sure about the intake gasket should I run a pressure test?