420a turbo problems

[Daniel393racing]

Ok so i have a 420a n/t with turbo conversion. Cars new to me, idles rough, runs poorely, seems to skip some, but what im worried about now is that somethings not right, when im about 3800-4000 the car wont rev higher, its like a rev limiter and then she just bucks and wont rev out. i dont feel much boost whatsoever, i think everythings working building right, but not allowing the motor to use the boost or whatever, this is all new to me, so somebody give me a starting spot please...

 

[Jonny J]

Boost leak test...

 

[Daniel393racing]

boost leak test huh? im guessing theirs ###### testers n whatnot but their also is the starting fluid trick right? juss spray all the vac lines and cuplers to see if theirs a leak ?
thanks dan

 

[GSTurbo1]

Check waste gate actuator to make sure it's hooked up, if not hook it up. Boost leak test, basically pressurize the system where the air is compressed after compressor housing. Worse comes to worst you need to do a compression test. You might have melted pistons or ringlands.

 

[Daniel393racing]

ok ill have to check wastegate and lines to make sure everythings hooked up, and lines and whatnot, afterwards if i have no luck i guess ill have to find a boost leak test and next a compression, thanks for advice, keep it comin
thanks dan

 

[dsmcrzy]

Do you know what your AFR is when this is happening? do you have any gauges you can get readings off? kinda makes me think of fuel cut but maybe thats just me.
Is everything set up for the 420A to be turboed? like what is it tuned with? Does it have a missing link or FCD? I see in your profile you have a JET performance ECU.. never heard of that. do you have a way to log what is happening?

 

[jayson427]

what are you using to tune the car tho? when its stuck at 4k and bucks then your map sensor is out of wack i believe. do you have a wideband? how big is the turbo?

 

[dsmcrzy]

when its stuck at 4k and bucks then your map sensor is out of wack i believe. QUOTE]

I agree. OP can you post up some good pics of your engine bay if you are not sure what we are talking about?

The MAP sensor is all the way to the left on the manifold. see if something is wired into it or has some sort of a spacer. the spacer is a missing link and is garbage compared to a proper FCD.

 

[Daniel393racing]

not excatly sure on the car, just got it and been looking through it, is throwing some codes, one is MAP sensor so im guessing something might be wrong with that i dont belive the gauges are fully hooked up, i think its running a bit rich beause of the smoke and whatnot once again i do belive it is setup, turbo, wastegate, intercooler and whatnot. i hear the car building little boost but its juss mostly coming out of the blow off valve, the car does have a missing link hooked up, not sure what FCD is.. and yes jet performance ecu, has part number and serial number from manufactuer, figured its legit, wideband im not sure off, and the turbo is a t3/t4 i belive, not excatly sure, once again all this is new to me but this is the advice i need, keep it comin dudes ^.^
thanks dan

 

[dsmcrzy]

FCD = Fuel Cut Defender it's an electronic signal conditioner that keeps the MAP from sending a +5 volt signal to the ECU. On a N/A car the map will read +0 volts to +5 volts depending on the manifold pressure. The MAP can't handle positive manifold pressure (i.e. boost) there for the ECU throws a code and the ECU cuts the fuel.

Here is a link to one.
http://www.symtechlabs.com/catalog/fuel-cut-defender-fcd-p-33.html

Also missing links don't always work. people have better luck with an FCD but missing links are cheap so people will go that way

 

[Daniel393racing]

Okay so i need to get rid of the missing link underneath the MAP sensor and get FCD to go in its place. ill need to try that. will that cure the major problem ?

 

[jayson427]

t3/t4 is a flange fitting not the size of the turbo. it should say something else on it, what about the brand? do you know about the internals of the engine? do you know how much boost the car is running?

 

[dsmcrzy]

Okay so i need to get rid of the missing link underneath the MAP sensor and get FCD to go in its place. ill need to try that. will that cure the major problem ?

I can't think of anything else that would throw the MAP code. I would also go through and do a boost leak test and compression test. Also make sure all the vacuum lines are hooked up correctly.

 

[Daniel393racing]

i belive its a garret..sounds about right..said to be on 14 lbls with 750 injec. pretty sure it has a internal wastegate, but its not working properly. its just staying shut or open, not moving. so i was going to go with the bolt on turbonectics wastegate ajustable 7-10 lbs that a buddy has. would i be able to convert it over to a external wastegate insaid of internal..