W.o.t. Stumble! Stumped

[GR8WHITE]

Hey Guys I Just Installed My Blacktop And Got It Running But Here Is My Question. The Car Idles Perfectly And While Revving The Motor Freely With No Load The Car Revs To Redline Like A Top, However When I Get On The Street At Half Throttle It Pulls Ok And Runs Alright But As Soon As I Go Wide Open Throttle The Car Falls On Its Face And Bucks While Backfiring, And The Car Seems To Not Spool Until Like 4400 Rpm. Seems The Longer I Drive The Car The Worse It Gets And With No Boost Controller The Car Is Boosting 9psi. Any Suggestions Would Be Greatly Appreciated. Thanks.

list Of Engine Mods
Blacktop Sr20det
Greddy Fmic
Greddy Turbo Elbow
3" Downpipe
Cat Delete Pipe
Apexi Noir Exhaust
Hotpipe W/hks Ssqv
Exedy Clutch
Greddy Ras

[DOHCsky]

sounds like a boost leak....check all your hose clamps

[NiteRaven]

You are in luck my friend. I just spent weeks and nearly lost my sanity solving the same exact problem.

http://www.240sxforums.com/forums/showthread.php?t=85811

Read that thread soak it all in. Come back in a week and let me know how things are going! :D

[xxsptcuztomsxx]

Try testing your coilpacks (with a new spark plug) for spark. My redtop did exactly what you are describing. I thought of everything. Then one day the car began to idle like it was firing on 3 cylinders or somethin. Tested the coilpack for spark and the 2nd coilpack did not spark. So i tested the same one with a known working coilpack. The spark plug fired! I solved the problem by ordering a used coilpack from Tophat. The next day, fired it up and bingo...revved like a charm...I assume the bucking and backfiring were signs that the coilpack was about to go out or was not firing with enough voltage.Eventually the coilpack went out all together thus creating the rough idle as described above. You could have a friend who also owns an sr and install his/her coilpacks temporarly to see if that clears up your problem.

Also check all your vacuum, IC pipes, and other hoses.

Hope this well help.
Let us know what it was..

[NiteRaven]

Coil packs are definatly something to check out. However he said his idle was perfect so I don't think that applies to his situation.

[GR8WHITE]

Yeah Thats Why I Am Stumped Cause Revving While Not Moving It Revs And Idles Perfect But Not Driving

[GR8WHITE]

Hey Niteraven I Cant Check Out That Thread Without Being A Member

[DOHCsky]

seriously.... check for boost leaks....my car did the exact same thing when i bought it. the kid sold it to me because he thought the turbo was shot. turns out the coupler from the cold pipe to throttle body was ripped, as soon as it boosted during WOT it feel on its face, under half throttle it spooled okay. the hotter the motor got the softer the coupler got thus letting more boost escape.

[xxsptcuztomsxx]

yea.....has got to be a leak somewhere. Check all possible ic pipe couplers. Also, make sure your blow off valve is tightened down good on the flange. You can also check the metal elbow inlet on the turbo. Make sure the gasket is there and its tight. Check your intercooler for leaks too.

[GR8WHITE]

Thanks Guys Im Off Tomorrow And Will Double Check Everything, One More Question If There Is A Boost Leak Will The Boost Gauge Needle Fluctuate Up And Down Or Still Hold Still On Correct Boost

[Enjin]

I had the same problem and I had a hole in a boost pipe. duct taped that joker and it ran fine.

the variable in your stories seems to be boost pressure, so thats what I bet it is.

[GR8WHITE]

Thanx Guys For All The Help, But I Finally Fixed It. Yesterday I Had To Put In My Walbro Fuel Pump And When I Pulled Out The Old Pump The Fuel Strainer Was Almost Black And Had All Kinds Of Crap In It So I Put The New Pump And Strainer In And Voila! The Car Runs Perfect, I Guess It Was Fuel Starvation At High Rpm. Thanx For The Help Guys

[xxsptcuztomsxx]

Congrats.....glad to hear you figured it out...no more grey hairs...lol