SOHCex20

I've recently been getting misfire codes with my DSM 450's running the hack on my greddy 15g kit. I clear the codes at work, and I boost over 11psi and the check engine light comes on for the MAP sensor, but I check the codes every week, and I get a p0400 and then an individual code for each cylinder. Could the MAP sensor be throwing off erratic readings because I boost over 11psi, or wouldn't that effect this situation?? Just seeing if anyone else getting misfire codes with their DSM's or could I be looking at a different problem here? I also just put in NGK's 2 step colder plugs, gapped a .028, new cap and rotor, and new wires. I want to get myself some RC 440's but don't have the funds right now, but if these DSM's are my problem, gotta get it fixed asap because I have to pass emissions and make sure I have no CEL.

By the way, I have compression readings of 190, 180, 175, and 185.


Modified by SOHCex20 at 12:08 AM 8/5/2005

SOHCex20

No other situations like this??

beepy

A rule of thumb: You should always ignore misfire codes (P0400, P0401, P0402, etc) as long as there is any other code on the ECU: Many codes can cause subsequent misfire codes.

So you are boosting to 11 PSI and getting a CEL? What fuel management? You will definately misfire if the ECU is seeing boost, and since you are using OBDII I know you aren't on Uberdata or Chrome, so you must be using an Emanage, FMU, or SAFC? If it is the FMU you must remember to use check valves to prevent the ECU from reading boost.

You are using the perfect spark plug - BKR8ES-11, so that isn't the problem.

SOHCex20

I'm using an SAFC with DSM 450's. So your saying, as long as I am away from 11 psi and my ECU reading boost, most likely no CEL for misfires will occur? Then my question is, if I want to continue boosting over 11psi and get those misfire codes, is there any way to eliminate the CEL using the hack over 11psi? Or will Uberdata, or Chrome have to be used instead? I'm not too familiar with Uberdata or Chrome, haven't been looking into it that much, but from what I see when people get it dyno tuned, a good 20 whp has been added on by a good tune using that. I guess a little more research will be needed before going that route, but as for now, is there a way to eliminate that CEL over 11psi using the hack or no?

tommy1

if you are running boost, you should have the check valves or a missing link installed on your map sensor.

I have a missing link that I'm trying to sell for 30 shipped, IM me if you are interested.

If I remember correctly, the stock map sensor should be good up to 11 psi, provided you have the check valves or missing link installed. If you go over, you have to install a 1 bar, 2 bar or 3 bar map sensor on your car depending on how much boost you are actually running.

SOHCex20

well I want to run 12psi consistanly and up it for the track, but I've been told I don't need a check valve if I'm using an AFC, but once it goes over 11psi, it goes into limp mode, so if I find out I can use a check valve for 12-13psi with the hack I'd definatly go that route to keep my car running smooth, and efficient w/o a CEL.