need help! supra running bad

03-16-2005, 10:17 PM

1st off - i have a 91' supra n/a with the 7mge motor in it and 5-speed that the guy i bought it from had the motor rebuilt about 5k miles ago after he spun a bearing , from what he claims. the car ran like crap when i got it.

what iv done - set timing at 10 deg / set idle at between 7-800 rpm / had origanal cat removed ( now running straight exhaust from header to apexi n1 style muffler in the back) / cold air intake conversion / cleaned and ported intake track / replaced fuel filter / changed spark plugs and wires / coolant bypass ( so coolant dosnt run through the throttle body) / ran injector cleaner through it and used seafoam in the gas tank .

the problems - choppy idle ( idles like i got some lopy cams in it) / exsessive blowby ( took off pcv and smoke was puffing out at idle then more as it revved) / wet oil-like residue in intake track (along with carbon like sluge in lower intake)-probly from the wet stuff drying / poor acceleration (gf's 4cl. tiburon seems more powerful

) / and when i stand on it it makes a wierd starving for fule -like sound and falls on its face around 5k rpm / also power seems like its only there from 4k up but then does the starving thing at around 5k . also has a rusty color in the coolant.

what iv done to try to fix it - lol everything , it seems when i disconect vacum from the "fpr" it cleans up the idle a tad but not much. (still runs the same pretty much throughout the powerband with it disconnected) . iv also tryed to adjust the "tps" but moving it clockwise makes it more of a turd and counterclockwise too much and it clunks when i shift and makes the pedal verry touchy (on and off effect so to say) . iv pretty much tryed everything i could think of and now i think it has to do internally due to the fact its not throwing any check engine codes?????

what i can think of - the mechanics at a local shop told me the egr wasnt functioning properly (stuck shut) but i dont think that has to do with this, but then again im new to the supra and learning as i go. the only think i can think of is maybe mis-adjusted valves, the famous headgasket problem , or when they rebuilt the motor they didnt let the rings seat properly ??? or faulty ecu.

anyway, im at a total loss for things to do or direction to go at this point and in need of some assistance from someone who deals with supra's or has dealt with supra's and has hands-on know how and knows the car specifacally.
any help from the forums would help me tremendously.

also, i have yet to do a compression test but will be verry soon and theres also a hose that disconnected and is capped off under the intake , im not sure where it goes cuz the only thing under there from my understanding is a vacum switch but that is already connected , and also cant seem to find any vacum tank under the hood if any of that helps .

thanx for youre time , any help would help or atleast a direction to go in would help tremendously.
I love the car and was gonna custom turbo it or just make it a n/a beast after i was done building my motor for my 70' cuda but wanted to make sure the engine was stable before i started heavily modding it .

thanx a ton
john
70'cuda- domestic beer of choice
91'supra- imported beer of choice

snafu54 · 03-17-2005, 10:41 PM

is the intake tight on the engine have you checked for vacuum leaks? what about the injectors? not enough fuel (bad fule filter) mabey.

03-17-2005, 10:50 PM

thanx for the reply , yes iv checked numerous times for leaks and the injectors were flushed when the engine was rebuilt .
the fuel filter was the first thing i changed when i got the car and still runs like crap.
I thought that was the problem due to the fact the car would act like its starving around 5k rpm's

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Dream Offer	Karma_Supra	MKIV Supra	22	10-17-2007 03:04 PM
MKIV Supra TT Daytime Running Lights??	MIX	MKIV Supra	2	08-30-2007 02:52 AM
supra running rough	finn	MKIII Supra	0	09-25-2006 07:10 PM
87 Toy Supra N/A, Running on 4 Cylinders	wilvelas	MKIII Supra	5	04-24-2006 02:40 AM
Im New, Going from a V8 to a supra maybe? Help!	Deadtoday	Non-Generation Specific Questions	9	05-24-2005 11:10 PM

03-16-2005, 10:17 PM	#1
cuda/supra#1 Guest Posts: n/a	1st off - i have a 91' supra n/a with the 7mge motor in it and 5-speed that the guy i bought it from had the motor rebuilt about 5k miles ago after he spun a bearing , from what he claims. the car ran like crap when i got it. what iv done - set timing at 10 deg / set idle at between 7-800 rpm / had origanal cat removed ( now running straight exhaust from header to apexi n1 style muffler in the back) / cold air intake conversion / cleaned and ported intake track / replaced fuel filter / changed spark plugs and wires / coolant bypass ( so coolant dosnt run through the throttle body) / ran injector cleaner through it and used seafoam in the gas tank . the problems - choppy idle ( idles like i got some lopy cams in it) / exsessive blowby ( took off pcv and smoke was puffing out at idle then more as it revved) / wet oil-like residue in intake track (along with carbon like sluge in lower intake)-probly from the wet stuff drying / poor acceleration (gf's 4cl. tiburon seems more powerful ) / and when i stand on it it makes a wierd starving for fule -like sound and falls on its face around 5k rpm / also power seems like its only there from 4k up but then does the starving thing at around 5k . also has a rusty color in the coolant. what iv done to try to fix it - lol everything , it seems when i disconect vacum from the "fpr" it cleans up the idle a tad but not much. (still runs the same pretty much throughout the powerband with it disconnected) . iv also tryed to adjust the "tps" but moving it clockwise makes it more of a turd and counterclockwise too much and it clunks when i shift and makes the pedal verry touchy (on and off effect so to say) . iv pretty much tryed everything i could think of and now i think it has to do internally due to the fact its not throwing any check engine codes????? what i can think of - the mechanics at a local shop told me the egr wasnt functioning properly (stuck shut) but i dont think that has to do with this, but then again im new to the supra and learning as i go. the only think i can think of is maybe mis-adjusted valves, the famous headgasket problem , or when they rebuilt the motor they didnt let the rings seat properly ??? or faulty ecu. anyway, im at a total loss for things to do or direction to go at this point and in need of some assistance from someone who deals with supra's or has dealt with supra's and has hands-on know how and knows the car specifacally. any help from the forums would help me tremendously. also, i have yet to do a compression test but will be verry soon and theres also a hose that disconnected and is capped off under the intake , im not sure where it goes cuz the only thing under there from my understanding is a vacum switch but that is already connected , and also cant seem to find any vacum tank under the hood if any of that helps . thanx for youre time , any help would help or atleast a direction to go in would help tremendously. I love the car and was gonna custom turbo it or just make it a n/a beast after i was done building my motor for my 70' cuda but wanted to make sure the engine was stable before i started heavily modding it . thanx a ton john 70'cuda- domestic beer of choice 91'supra- imported beer of choice

03-17-2005, 10:41 PM	#2
snafu54 Intake Join Date: Jan 2005 Location: arizona Posts: 32	is the intake tight on the engine have you checked for vacuum leaks? what about the injectors? not enough fuel (bad fule filter) mabey.

03-17-2005, 10:50 PM	#3
cuda/supra#1 Guest Posts: n/a	thanx for the reply , yes iv checked numerous times for leaks and the injectors were flushed when the engine was rebuilt . the fuel filter was the first thing i changed when i got the car and still runs like crap. I thought that was the problem due to the fact the car would act like its starving around 5k rpm's