DETONATION

Seafoamed a month ago and the car ran fine
Lately it stalls when I back up and sometimes when I come to a fast stop?
It seems to idle around 500 but when the car is moving really slow it drops to 300 or stalls.
when it stalls the check engine light comes on but when I start the car it goes right off "car is a 1993 " so i dont know if not being OBD1 has anything to do with it. I SEARCHED ON THE SITE
Ive looked through all the vacuum lines and they seem fine.
Changed the plugs again
Went to change the fuel filter and its rusted on but there is no rust anywhere else just on both sides of the fuel filter.
"not even PB Blaster is working" WTF the fuel line side seems to be 14mm and its stripping not budging at all on either side.
I really am stuck here and I dont want to have it get worse and get me stranded at work or something

DETONATION

never happened to anyone else?

DETONATION

I got the Fuel filter on and the stalling situation didnt change. I took the maf off and used MAF cleaner and put it back in then the car was really really bad. Spuddering and missing the car was running even worse and wouldnt stay on at all. The check engine light stayed on this time so I jumped the diagnostic port and it gave me a bad MAF code.

DETONATION

I changed the plugs and changed the MAF and the car seemed to run fine. When I changed the plugs I noticed that they were really really black and couldnt have been running right.Maybee that would explain the all of a sudden bad miss? I asume because they were black that the car had no problem getting fuel so I ruled out fuel pump in my head so far at least.On the way back to my house from the friends house" I had to leave it at because thats where I cleaned the maf" it stalled about 9 times. No studering or anything it would just stall again. How can I figure out whats wrong if theres no code? My grounds are ok and so are my vacuum lines.

DETONATION

I brought it to a pretty good local shop this morning at about 7am and they still havent figured out whats wrong and its about 5pm
They charged me $114.00 just to tell me that they think its the Maf and that it will cost me nearly $700.00 after everything. the car is no throwing a code though its just stalling

redsc400

search "fuel pump ECU". my sc300 would have mystery stalls with no CEL's thrown....after some research I decided to swap my fuel pump ECU (literally takes 30 mins) and no more stalls ever since....

DETONATION

thanks for your help at least you are trying to help me. Ill check into it

redsc400

when you say you seafoamed....did you change your oil / plugs afterward?

since it breaks down carbon deposits...a loose chunk could be wreaking havoc on your internals. change it asap if not already done..... it is also reccomended to change your plugs right after seafoaming bc they have a tendency to get gunked up.... good luck if you have a SC300 its a huge PITA to get to them....

TheMole

iTrader: (13)

Yea it says that he changed the plugs in the first post. Do you have an sc300 or an sc400? You shouldn't be using the maf cleaner if you have an sc300 since they use an afm.

snsrushing

I have a similar situation, the a-hole that owned my 92 SC400 before me neglected it, I pulled the original spark plugs, etc. off it and it helped a little. I also started tweaking the TPS and it helped a little more. But now when at a stop light it will go from idling at about 800 and then drop down to 300 or lower real quick and then bounce back up for a little then bounce back down, same for driving around in a parking lot. I dont know if its related to when I get on the gas it seems like it misses. I'm trying to track down a fuel pump ecu online but its not coming up.

redsc400

PM aliga he probably has a few of them

snsrushing

I disconnected the AFM and its driving normal with the exception of the trac light on and so is the check engine but I've had it up to 60

User1321989

iTrader: (1)

you have a vacuum line leak.....spray some carb cleaner over the engine and see if the idle picks up.... when it does that will tell you where you leak is.....your TPS sensor may be failing as well

JspecSC3

iTrader: (4)

Something tells me it may be the TPS sensor as well. I helped a buddy with the same problem on his SC300. It would have a rough idle and then the RPMs would drop almost stalling the engine at a take off. Replaced the sensor and the problem was solved.