I've been having problems with my truck and have a question. My earlier thread about fuel pressure is HERE When I went for a test drive after installing a FP gauge, I kept getting P1211 codes. Every time I ran it hard, it would throw a code. I had the MT2500 hooked up and had my GF watch the data stream.. Specifically ICP and IPR %. I was able to get the ICP up to 3,300PSI and the IPR percentage was up to 63. At idle, ICP is at 480 and IPR at 9%

The P1211 code only says above/below desired. WHat are the upper and lower limits?

 

P1211 is a normal code you get if you have your engine chipped or have a programmer or tuner.. Disconnect the tuner, clear the code and run it hard again.. you probably won't get the code.. (i think the stock HPOP can't keep up with the demand when you drive it hard and you get the code..)

 

I just found a great write up on the P1211 code HERE


I should have just used the search earlier...

 

Thanks!

That's probably what's happening.. I have an EVO tuner on it..

 

I think that is some mis-information. Right now as I type this, my truck is having the same issue with throwing the P1211 code. The PCM that was in the truck had an Edge Evolution, but the PCM fried. I then replaced it and the PCM is not chipped. The problem I am having is that once I get the truck up to normal operating temperature, after about 30 minutes of messing with it trying to get it to start, my truck will then idle. Once I get the RPMs up to 1000 RPMs, the truck dies and in some cases, it will throw that code.

 

Anyone else got this code for any other reason than the "chips" ?
I haven't ran the DTC since I cleared them...but just wanna be on the look out for potential other issues running a chip.

 

Many things can cause the P1211, it's a case-by-case thing. A hot tune is a very common cause, though.

 

Low fuel pressure is one of the most common causes of the P1211 popping up. It can also be caused by HPO leaks, failing IPR, failing HPOP. It isn't often the pump itself, but it does happen from time to time.

The code is triggered when the PCM is unable to control ICP by commanding the IPR duty cycle higher or lower, such as what happens when there's a large leak. The ICP keeps dropping, so the PCM commands the IPR duty cycle higher and higher to its maximum. If the ICP is still lower than desired it is considered by the PCM to be uncontrollable, and the code is set.

 

Pikachu: My personal experience with low fuel pressure causing a 1211 Code. When inside delamination of my van's steel fuel tank clogged my fuel filter causing fuel starvation, the code I got was 1211.