Turboed FS-DE seems too lean Help!

Nickson

Member
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ES-GT turbo 2002
HI, (sorry for my english)

Last summer I installed a stock MSP turbo kit in my ES-gt. I'm running it at stock boost 7-7.5.
I have a FMIC, custom alu. piping, a Forge BOV and a CAI
I juste spend 60$ to learn that the PCM has already the right version...
Installed the little one way check valve that goes near the throttle body

During the dyno run to test it we noticed that it was running lean for too long before enrichiing and it was never becoming rich if I don't WOT. 2 weeks ago I blew the engine when I was pressing the gas pedal half way in 4th only past the point that it start to boost much. I always wondered if it was normal that I had much more air hissing sound when not WOT than if I WOT?? It seems that I burned the valves from cylinder 2. I was running on 3 cylinder after that and the valves stayed open according to the compression test.
It was burning much oil from the valves seals (I think) from long time ago (before the turbo) I thought that maybe the seals were not alowing lubrification on these vavles or something like that. OR, I was way too lean when not WOT and it burned.
I also had a FSH9 intake cam in it from when it was N/A. Should i put it back if I already have it?

Now I have the 2nd engine installed and I don't want the same thing to happen. I would like to have true answers for my problem.
The engine seems ok when it's cold but when it get hot it seems to stay too lean. Even if I press it hard.

Questions that nobody seems to really know it:
- are the injectors the same on FS-DE & FS-DET??
- Are the O2 sensors the same??
- Is the MAF the same??
- Only the msp ECU manage the differences for the turbo??

Maybe the MAF is too dirty ? Help I'm lost. There should be a solution beside buying a expensive AFC

Thx
 
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Questions that nobody seems to really know it:
- are the injectors the same on FS-DE & FS-DET??
- Are the O2 sensors the same??
- Is the MAF the same??
- Only the msp ECU manage the differences for the turbo??
They're all the same. I assume you're using the MSP ECU or some other kind of engine management? If not, that's your problem but if you are it sounds like you have a leak somewhere; exhaust or vacuum (or both!).
 
How do you know if you are running too lean or rich. Do you have any lambda readings to reflect this?
 
Yes i got the MSP ECU !
since the last post I also have a new MAF, new O2 sensor, New boost sensor, new pcv valve, new high flow cat.

Already did some test with widebands and it confirms that I don't go in open loop at time. only after 3800 rpm. The engine have the time to heat a lot. I hear much the boosted air as it's not burned with enough fuel. And i got poor acceleration. A normal MSP should go in open loops as soon as it sees boost. With my narrowband A/F i know it's s*** but i can see when the car is in openloop.

Sometimes I got it to work correctly after trying diff. things but it's like if the ecu compensate the wrong way.

Also have a new problem. After cleaning all electric connection and checked vac lines and plugs and piping. I'm running too rich on the highway. unable to hold a 70MPH steady when there's not much load and no boost it becomes way too rich when going in open loop and the car starts to buck a lot.
I cleaned my BOV yesterday and i think i found why. The green spring is almost broken in the middle only a little bit holds it togheter and it's not straight anymore. but it's not the main problem because the spring was fine before. Maybe that's the problem why the car is too rich now in city driving when it open loops. The car backfires and even worst it has a very hard but short hesitation when shifting when I accelerate at WOT.

I don't know where to check next. I'm thinking of the throttle position sensor and maybe coolant temp sensor? Or maybe a defect ECU ?

It gives me lots of check engine related to the intake manifold.
P0108 -> boost sensor high output voltage but it's new and it tell this whit the old too so it's not the sensor
P0660 -> intake manif tuning valve circuit open. Even if I cleaned and scratched the connectors contacts.
another one for system too rich

i don't have the code for the EGR valve. I'm SURE it's the problem. How do i get the code to get it remplaced free by mazda? unplug it's connector until the code pops ??

Thanks for your help
 
Wow, um first off the MSP ECU does not "automatically go into open loop when it 'sees' boost" Open loop is triggered but a certain throttle percentage as well as being above a certain RPM (about 4500-5000 RPM I believe). Back before I had my AFC I could get into boost without the car into open loop.

Anyway, where is your BOV in relation to the MAF? If it's after the MAF (flow direction) and it's leaking then that would lead to lean conditions at idle and during cruise because air would be drawn in through the BOV that is not getting read by the MAF. This would also lead to rich conditions while boosting because air would be escaping through the BOV so less air would be entering the engine than the car thinks.

As for those other codes it does seem like something is up with the EGR - the boost sensor is referring to the EGR boost sensor. Make sure that vacuum lines running to that are all connected and in good condition. I'm not really sure what the other code is.

Lastly, I'm sure you already know this but ditch the narrowband as it could really be saying anything. Chances are it will always read "lean" at idle and "rich" under boost so go out and grab a wideband so you can really know what's going on.

I hope this helps some.
 

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