I recently did alot of work to my 2008 Evo gsr
Plugs
Injectors idx 1300
Aem fuel rail
Map fuel rail install kit with inline filter
Manifold
Stock frame turbo
3in downpipe and test pipe
Walbro 450 pump

I have this issue where it seems only once the engine is warmed up and super intermittent I will start the car and it will fail to achieve idle and gurgle around under idle rpm for 10-15 seconds and then die. Reving it doesn't seem to save it or make a difference

I'm also throwing the random misfire code. I changed the plugs twice since. Running the iridium.

I also have almost a knock sound when I'm in the car I've heard you can get reverberation from having a straight test pipe so I switched it out for a resonated one but it's still there although not as loud. The sound disappears when I get out of the car.

I have searched on here evolutionm forums and Google and tried the things mentioned. I replaced the fuel pressure regulator and redid the vacuum lines. I reached out to my tuner about a compression test but was wondering some other things I can look at.

I do have some random clunking noises which I think is the downpipe hitting the tie rod heat shield thing but I'm not sure if that would contribute to the code

I have no surging or stuttering from the engine or any other idle issues. The car runs great other than these things

Thanks in advance


Update:. I did a compression test and have over 120 in all cylinders. I was really dreading that test but looks like engine isn't the problem. Any suggestions?

Anyone have any ideas on this? It's driving me crazy. It no started the other day for almost 30 min. And sometimes when I'm starting off from idle it will randomly lean all the way out and engine will stutter. Tuner recommended I replace the thermostat which I have ordered and will do. Just seems like an injector issue or fuel issue to me?

Sry I posted the thread from evo x forums. No one would respond there. I've replaced every gasket and vacuum line. I had a smoke test and my system is sealed.

 

@intafocus Whats the exact code? Have you considered running a log off the ECU & showing your turner?

 

The exact code is the random misfire code. P0300. I am replacing the thermostat just since it's easy and cheap and then I'm going to go back and have him actually ride with me so he can see the problem first hand and get him to put it back on the dyno.

Here are two things I also considered.
I have the fuel filter right off the fuel rail so I don't know if that's too close and it's causing it.

Also the fuel pump install on these cars is kinda wonky with the clearance between the pump and the grommet it connects to so idk if my hose got a little kinked maybe

Or the injectors where not tuned right at idle , idk

 

When the tuner rides w/you i would hope that his laptop is connected to the ECU vs waiting to load on the dyno?

 

I haven't ridin with him yet. I haven't been able to be there while he looked at it last time. I replaced the thermostat and no change. I have for sure made it a point to be there next time I take it in. Hopefully tomorrow

 

Sometimes when I start it up it will surge too like almost die and then jump to 1kish then stumble again in that cycle until I rev it out. These are all things that the car never did before the modification

 

If he's a true tuner, my guess is that he'll have his laptop w/him. Likely something pretty simple. Too bad we havent had you on the boards as we have many members that are very X oriented including reading ECU logs

Keep us posted please / Cheers

 

Anyone have anymore ideas for what I can check? The tuner said he doesn't see anything wrong but it's missing like crazy at idle and wanting to die and everything

 

I've done the idle relearn procedure 4 times

 

Is there anything else mechanically I can check?

 

Have you done a boost leak test?

 

I did a smoke test and there was a slight leak in my blow off valve so I replaced it with an oem unit. I'm not sure if a smoke test and boost leak test are one in the same

 

TBH I don't know either. A boost leak test pressurizes your system to max boost plus a few psi, and from the turbo inlet back. So capturing pretty much the whole system, minus the intake pipe. So if the smoke test did all that, but with smoke, then it's the same.

I've never heard of a smoke test being done instead of a boost leak test though.

 

A smoke test will find any leaks at atmospheric pressure (broken or disconnected vacuum lines, leaky gaskets, etc.) but it won't find stuff that only happens under boost (like a loose hose clamp or a cut/tear in a silicone hose coupler). It sounds like it could be a failing coil pack or possibly a fueling issue. If it's intermittent it's probably not the tune. If I were to guess its a bad coilpack.

 

Missfire code could just be associated with the poor starting. If it was calling out a specific coil that would be different, but random makes me think it's more of a symptom. When ever I get a random missfire, its been associated with my fuel tuning. It sounds like your tuner thinks your thermostat is getting stuck open and letting the motor flood with cold coolant, making it read cold and spike fuel. Could be, that would show up in the log, before cranking it would read hot, and then you would see the temp drop quickly.