something wierd is afoot ...

heres the details
88 turbo II
recent rebuild/port from rotaryressurection
walbro pump rewired
safc (tuned for idle mostly)
sans emmissions
TB mod
racing beat full 3.15 turbo back exhaust
TID
that should be all that would affect performace as far as mods go

here we go

car runs perfect when not in boost ... as soon as i hit more than 3-4 pounds the car acts like its boggin down ...as if all power is lost ... im hitting the boost, but the car isnt responding to it ... almost like its losing gas or the timing is way off or soemthing ...
my car is also leaking hella oil ... so i thought maybe the turbo died and is spittin out oil .. ive checked the turbo for end play and what not and its good .. no front to back and no side to side play ... ive also checked my TID and my intercooler for oil , and theres none there

could it be the pressure sensor? what happens to the car when those go bad?

i have an safc with ALOT of fuel taken out in the 800-1200rpm range to assit with the walbro i have, but i doubt that would make a difference ...

and i have added fuel up top around the 5000 rpm and up range .. but just a little big .. maybe 4 % or so ... so surely that wouldnt make that big of a difference

what all could make the car not respond to boost, or respond poorly to boost?

i know my plugs are close to fouled if not already , but surely that alone wouldnt cause the car to just not go .. especially since the car runs great when not in boost?

any ideas?

 

also .. could a faulty leading coil cause this?

i hear that the 2nd gen coils are hardcore and rarely go bad, but the ones in the car now are most likely the ones that came off the showroom floor, and that was 197,000 miles ago.... maybe thier day is done?

has anyone ever had the leading coil go out on them??

 

i also noticed while setting the timing that the light was firing kinda irregularly on the leading coil ..

that cant be a good thing ???

 

The light is firing irregulary then you could be losing spark at higher RPMs.
You might check the coils as per the FSM and replace the plugs/wires (this being a rebuild they should have been changed at least once).

It kind of sounds like your hitting fuel cut, but that seems really odd..

 

its for sure not fuel cut ...ive felt that before ... and it does seem kinda like fuel cut as far as the feel, but im hitting 5 pounds of boost before 5k surely , and theres no way fuel cut is coming on that quick ...plus i have an FCD

and the plugs have been changed several times since the rebuild ...
atleast 3 times .. they keep fouling out due to my idle dumping so much fuel, which i have corrected in the safc that i have ...

i was gonna replace the plugs, as im sure they need it, however that doesnt seem to be the lone problem ..

im gonna go research how to test the leading coil so i can see if thats the problem

has anyone ever had a bad pressure sensor? or a bad coil?

does my symptoms sounds like either of the two?

 

My first guess - fouled or worn plugs.

A cheap AFR gauge will help help spot maybe dirty secondary injectors.

Bad dash boost gauge - common.

Bad pressure sensor - very rare.

 

Tap your S-AFC blue wire to the boost signal & you can verify the value.

 

im not reading the stock guage

ive got an aftermarket guage mounted up ...

it was actually just put in a few months ago , so i know its good ...

i'll change out the plugs tonight and hope that helps ...
im also going to check the leading coil and test it ..
i was hoping it wasnt a bad pressure sensor, as that just seemed wierd, but since i know its not my turbo theres only a few other things to check really

question still open about what the car feels like when a coil goes bad or is on the way out ..???

 

I just posted this on a similar problem:

The TPS may have a perfect idle value, but it is worn & has a dead spot further up in the sweep, you will get intermittant fuel cuts.

See the linked video > short video

 

Sounds like you are getting boost spikes and hitting fuel cut. Did you replace the line that goes to the pressure sensor? It should have a small pill in it to reduce boost spikes to the sensor. If you replaced the line, the pill may be gone.

-Joe

 

Did you happen to tune this SAFC with a wideband? Or did you use the Butt Dyno method?

 

so if your plugs are fouled it will hessitate like that? I flooded real bad not to long ago and cleaned the plugs however now right when I hit boost mine does the same thing his does. I've:

Changed injector plugs
have the restrictor pill in manifold end of the vac hose
tested and set the tps
wired in resistors.
have an rtek 1.7


all this and still my car does the same thing his is doing. will idle and drive perfect but as soon as I start to boost, bam my wideband hits 21 and all power is gone then it comes back when I let off the gas. THis happens inbetween 3200 rpm and 4000 rpm.

anymore help on this subject would be great!

and for those that have been paying attention to my thread my turbo smokes as well. this is wierd, two people with the same exact problem.......well kind of, mine won't get any boost.

 

no i cant get boost to go over 7 now ..

as soon as it gets close to 5 psi i get the drained power feeling ...

more like 3 psi or so ...

therse no way im boost spiking and hitting fuel cut ... i have an FCD and havent hit fuel cut since ... before this started happening i was hitting 10 all day long and loving it ...
the highest it ever spiked was 11 .. and it wasnt really even a spike just more like boost creep


i didnt tune with a wideband although thats next on my list to get .. however i didnt add any fuel anywhere near the rpm range where this is happening ..

i mean i can rev all the way as far as i want, just as long as i dont get into boost

i only added fuel starting at like 5500 and up

 

link doesnt work ... do you have another link by any chance?

 

well i pulled my plugs and they were covered in oil

apparently i put too much in last time i changed the oil .. however i put the same amount that i always do ... not sure why this time was so different

anyway the leading 1 plug didnt look too bad other than being foulded, the leading 2 plug however was covered in oil ... as were the trailings ...

i took them all out and turned over the engine to spit out the access, going to clean them and put them back in tomorrow ... then put some MMO in the oil and let it idle for 20 mins or so, then immediatly change the oil and put in new plugs ... hopefully that will be the end of my power loss ...

but now beings worrying about the freaking leak out of the oil pan ..
thats a pain in the ***!