Hey guys im hoping somebody can help me with a problem im having. I have a friend that bought a wrecked evo that was previously tuned about 3 years ago. My friend got his evo running again but was having problems with the way it was running. I told him to get the cable and software and i would help him fix everything.

So he gets everything and he does some logs and emails them to me "He currently is out of town for a job for winter". When i get the log there is 14 or more counts of knock from 4500-7500rpms which blows me away!

The problem is from around 4000rpms up to redline the car spudders terribly. Since the tune was so far out of whack anyway i decided to flash the stock 8 map back to see if it would clear anything up. The bad news is it stills is having the spuddering problem.

I had him make another log and send it to me and everything looks allot better then before as far as knock but the problem still exists so im hoping somebody can throw me some ideas.

He says that he can feather the throttle and as long as he keep the boost under 13-15lbs it will climb to redline without spuddering but as soon as it kits the 13-15lbs it spudders.

Also he just told me that he thew a Random Misfire DTC.

So what is everybody's thoughts? Any help is appreciated and thank you before
hand!


EDIT: I attached the log that he sent me so you can see whats up.
Chris

 

well, the only thing right now i can say is that have you looked at the ignition components and fuel components. Maybe the vacuum line to the FPR is disconnected or you have bad connections with the ign. wires. Maybe ur MAF sensor is clogged too. also check for boosts leaks. Check some of that and see if anything is messed up. Good Luck

 

start with checking the easy things, like mentioned above. plugs, wires, fuel. things that are effected with increased loads.

 

Thanks Guys. I would hope he already checked that already. Sometimes you give somebody the benefit and forget to ask the simple things..lol..

Just called him and he said the changed the plugs. He looked over the vaccuum lines and they all look good but that is just what he was able to see from the top of the engine.

Here is something new though. I guess when the car is cold it will run perfect no breakup no spuddering nothing. Soon as the car gets warm all hell breaks loose. I wonder if it is a o2 sensor?

Chris

 

I also find this very interesting. In the log he sent me this is the Air Volume log. Let me know if you think this looks a little weird..lol..




Chris

 

THis problem plagued me for 2 weeks!!! Here is the fix:

Open EcuFlash, goto Turbo Settings, and increase your boost control offset and your boost desired engine load. These two numbers added together will give you the load cell where the ecu will start to cut fuel. As soon as I increased these to a load that I will never hit (320), problem was solved!

Attachment 116121

 

With a stock BCS that will stop the ECU from limiting load under certain conditions, but not fuel cut. "Fuel cut" is controlled by the boost limit table. Your boost limit table might already be maxed out if it was tuned by some tuner already and that is why raising these tables might seem to solve the problem.

 

Incorrect and really bad advice actually. Please don't do this.

Those tables are the load targets for ecu-controlled boost. If you are using a MBC or Electronic boost controller, changing those tables will do nothing at all to the operation of your evo.

If you are still using ecu-boost, but with the stock boost lines, it won't do much either, except for take out a factory safe-guard (the ability to lower boost if the load is too high)

The "fuel cut" table is called Boost Limit.

To the OP, check the spark plugs and make sure they are the correct ones and gapped correctly.

 

Might check for a vaccuum leak (not a boost leak) When you boost your intake pressurizes after the turbo going towards the intake mani and engine, however the intake plumbing maintains a negative pressure vaccuum. At lower rpm this woulnt be an issue especially in closed loop. However opening up the throttle plate would create a higher vaccuum especially on boost and the unmetered air entering before the turbo in the track would cause an overly lean condition perhaps causing your stutter via just plain being lean, or ecu attempting to correct this issue. I would make sure that all of the intake is airtight.

The above posts are good advice too, is the car modded at all, or stock?

 

i would say take off fuel cut and mainly check your plugs regap to like .24 or .22 BPR7ES plugs

 

I am using a GReddy Profec B-SPec II and changing those tables had a very immediate and very direct effect on my evo. IT FIXED THE PROBLEM.

 

If you're using an EBC, changing values in those table wouldn't affect jack schitt on your car. Stop giving bad advice, since you don't really know what you're talking about.

To the OP, you need to tell your friend to start with regular things - check plugs, boost leak, and check if the DV(BOV) actually holds more than 15psi of pressure.

 

Wait a second here! So, you're telling me that I'm hallucinating? I had the EXACT same issue as the OP and by changing nothing else besides those tables, the issue was resolved. I'm not gonna say that it makes ANY logical sense here, but the bottom friggin line is, the problem disappeared. Coincidence? Maybe.

 

Def check the gapping of the plugs, i think he just threw them in there and that is misfireing....gap them to .26, have him pull all 4 and recheck the gap before going any further. or adjusting the ecu

 

Def check the gapping of the plugs, i think he just threw them in there and that is misfireing....gap them to .26, have him pull all 4 and recheck the gap before going any further. or adjusting the ecu

^^ definately check this


Wait a second here! So, you're telling me that I'm hallucinating? I had the EXACT same issue as the OP and by changing nothing else besides those tables, the issue was resolved. I'm not gonna say that it makes ANY logical sense here, but the bottom friggin line is, the problem disappeared. Coincidence? Maybe.

^^^ weird if this works, not certain, but honestly i dont think this installing an EBC will cure ur problem.