I have a "Check Engine Light" on my 04 with 17k miles. The codes are P0171 Fuel Trim System Lean bank 1-B, PO174 Fuel System Lean bank 2-B, U1096 Loss of communications with IPC and U1160 Loss of Communications with LDCM. According to dealer service, due to the fact that I am using a Vara Ram my Mass Air is "contaminated" (from the oil) cannot be cleaned and must be replaced. They want to put the stock air box back on and replace the Air Mass -- price approx. $900.

My first thought is to use throttle body spray cleaner. Does anyone have a suggestion?

 

contaminated by what oil?
Have you been oiling your vararam system again?


I run a vararam system also........I may have seen a system bank code once .............I dont think ive seen the code youre speaking of.

 

I just followed VaraRam's instructions -- used PJ-1 Cleaner and Oil. How many miles do you have on your VaraRam?

 

My car is pretty much a garage queen, sees weekend driving when the weathers fair.
Ive been having the vararam system for over a year, one of my first mods.
But I never have cleaned it with oil. Most I do is wipe armor all on the black parts to keep em looking new.
I dont put anything down the tunnels.

 

If you need a replacement MAF. Buy a used one on e-bay..... $50 to $75 should get you one.
But They can be cleaned with aerosol throttle (Assuming they are no more delicate than on my C4)

 

He is talking about using air cleaner oil on the filter. It is a foam filter and will not filter efficiently if you do not oil it. You have to be careful not to over oil or it can accumulate on the MAF wire and cause problems.

I would try taking a cue tip with rubbing alcohol and cleaning the MAF. Then tighten all the fittings. Reset your codes and see if that helps.

Not saying the dealer is wrong but they have a service bulletin that tells them if someone has an aftermarket filter then this is the problem. That is probably all the diagnosing they did. I would try to fix it myself before I went the route they suggest. Clean the vararam filter with TSP to get the old oil off, then dawn. Let it dry and very lightly oil it.

 

Who did you get it from? I got mine from LAPD and got the foam filter, my instructions said to oil, but that did not seem correct. I asked LAPD and they said you are not to oil the new foam filters. To clean the mass air get some electrical contact/parts cleaner from radio shack or where ever you can get it and just spray it on the sensors.

 

"Long term fuel trim makes coarse adjustments in order to maintain an air/fuel ratio of 14.7:1. If the PCM detects an excessively lean condition, DTC P0171 or P0174 sets."

What this means is that the VaraRam is working as designed and bringing more and cooler air through the tunnels into the MAF and engine. This causes the mixture to lean out and the PCM tries to compensate by adding fuel. It can only do this up to 25% of the trim adjustment. Beyond that, the PCM throws in the towel and indicates it can make no more adjustment to the trims by throwing the P0171 and P0174 codes. This lean condition is normal for the VaraRam although it generally doesn't send most engines into an unrecoverable lean condition that throws those codes.

The solution is to tune your PCM for the added air. The PCM builds a table of Long Term Fuel Trim (LTFT) values and stores them as a reference. Without resetting them, you won't be able to get the PCM to learn the new air flow and adjust for it. You can do this kind of tuning by getting a scanning/tuning package like EFILive or HP Tuners and doing it yourself or having an experienced tuner or friend do it for you. It's a somewhat expensive solution but the only right way to do it.

A couple of things you can try right off the bat before going this route. First, pull the filter out and confirm it is properly (not overly) oiled. Take the MAF off and get a can of electrical contact cleaner and spray the wires well (and carefully) to get any contaminants off. You can use alcohol and a Q-tip but I don't recommend touching those wires to someone unfamiliar with the MAF. Next, put everything back together and make sure all your connections are tight and sealed. Then, reset the codes on your DIC, disconnect your battery for 30 minutes and reconnect it. That will reset your PCM and trims so you can start rebuliding the trim tables from zero. It will take at least a few days of driving to do. Hopefully the codes won't come back before it's had time to try and adjust.

Ultimately you will need a tune to get the most out of your VaraRam. But I seriously doubt you need a new MAF unless someone broke it during the VaraRam install.

 

Thnks for the information. As it turns out, the problem (Check Engine) was caused when Jiffy Lube checked the filte and then installed it backward. When I checked the MAF, it was blocked (about 50%) with leaves. After cleaning MAF and filter and resetting the codes, the check engine lite stays off.

Regarding the LTFT, from your message it appears that I will still need to tune my PCM for the VaraRam. I have been trying to rationalize buying a scanning/tuning package for some time. I guess I have found rational.

Thanks agian,

Steve Hicks

 

Did LAPD mean NEVER OIL (even after cleaning) or just not oil a new filter? Are you using VaraRam's filter?

 

another 1 caused by the boys at Jiffy Lube

 

It did not come with oil, and you never add oil. My guess is that Vararam makes the filter for them.

 

People actually take their cars to Jiffy Lube? Yikes! You know what kind of peeps work at some of those places? Man, it's a Corvette... stick with the dealer or do it yourself.