I have had a few previous internal wastegate cars and on my 8 mr i noticed that if i am in 6th or cruising and decide to ease on the throttle to change lanes or get off a exit ramp and go from like 3rd cruising to WOT my car starts pulling like a mo fo then all off a sudden brick wall like boost or fuel cut im at 23psi and 11.1-10.5 afr what could cause this? but if i start from a dead stop and hammer it, it never does it at all highest boost ive seen on tru boost was 23.5.

 

compressor surge maybe???

my evo doesn't do it...but my old dodge 12v diesel sure did! haha.

 

Check your plugs, do a boost leak test. Try to get your AFRs out to 11.2-11.4.

 

too much load probably.

 

Do you have a double pumper installed?

-Acree

 

I have a similar issue on my 05 VIII MR after I installed a FP HTA 71 cartridge to replace a seized stock turbo. I also got the 18psi actuator which I installed incorrectly and was getting huge over boost due to me forcing it in place( waste gate always shut !! Ooops!!) . I am thinking along the lines as the other posters it might be a boost leak, so i ordered a leak boost tester from

Turboboostleaktester

Didn't feel like making my own plus this can be ordered with NPT fitting or tire stem valve.

Hope this is what the issue is.

Athanasios

 

plugs or ignition system mine did the same thing or maybe in the tune?

 

^+plugs mine did that too.

 

recheck your gap .021 (NGK plug) seems to be perfect for me at 38+ psi w/ a spoolin up c.o.p.

 

I'm thinking misfire... you have a wideband, right? Normally misfires will show lean (as fuel hasen't combusted) readings, are you getting that?

Just double checking, I understand you are mid 10's

 

Can't speak for the OP but on my set up its not lean at all, its between 10.5 and 11.5 monitoring with an AEM UEGO digital gauge. But I do probably need new lugs 92k and still original.

Athanasios

 

Well i think you guys were right , at least about my issue.

went and bought new plugs. Tried to install them tonight and on the first plug wire i tried to pull this happened.

Wire and boot with old and new plug.


Close up of burnt wire.


As you can see the small protuberance on the new plug is not there on the old plugs, burned right off.
I guess 94k miles will do that to plugs


I also noticed the plugs that had the wires and not the coil on top had brown heat marks on the ceramic, also those electrodes were not as eaten up as the wire ones.The burnt one in this pic was also the one that had the burnt wire, see the black carbon from the arcing!!


So i have to order new wire set, i really want the ralliart ones but can't find who caries them in the USA.

Athanasios