need help w/ 89 SOHC

[kernan240sx]

Car shakes occasionally on startup like its running on 3 cylinders. Only does it on hot starts , not cold starts. Had a tune up, replaced coolant temp sensor, compression is 180 all the way across. any idears?

[180sxn]

MAF, ground, fouled plug, rotor and cap???what have you checked?

[kernan240sx]

havent checked MAF, but my car will rev above 3500 so i havent really considered it being the MAF. During the tune-up, plugs and cap were checked and a plug was replaced. The problem only occurs if my car is driven in town or to school and sits for less than about 4 hours. If it sits over night or for a longer time, it starts up fine.

[kernan240sx]

car is getting considerably worse. Today i was driving in town and i started it up and it was shaking really bad and lots of smoke was coming out of the exhaust. It wasnt overheating (i made sure to watch for that) but it was idling very rough and i could just see the smoke coming from the exhaust. My car was backfiring too.???? I need help...i wanna fix this car and sell it

[philseed]

had a similar problem this week with my DOHC.... car was idling rough... and some white smoke.. check you fuel injectors... mine was shot on the #2 cylinder

[kernan240sx]

could you visibly see your injector leaking? Because i cannot..

[justy90240sx]

check the connections on each injector by wigglin the ele plug and the injector while the car is running if it starts running differently theres your problem, also try sprayin brake cleaner (while engine is running) on vaccum hoses and injectors, if engine idles up you have a leak. if you find nothing there then do a compression check a spark check and check injectors with noid light. also on the ka24e they are known for the coolant temp sensor goin bad and the maf sensor gets dirty and has to be cleaned with brake cleaner. let me know what u do or dont find and ill do my best to help you. i know these cars pretty well i have a 90 that i think has had every problem at some point. have you check the coolant in your radiator could be a head gasket as well, when mine went it would only smoked some times

[kernan240sx]

compression is 180 on all cylinders, had a tune-up done recently (changed out spark plugs and adjusted timing), replaced coolant temp sensor, coolant level is fine and the car hasnt overheated so i dont think its the headgasket. I really think its fuel related. It seems like it is getting WAY too much fuel... could it be possible that my fuel rail is leaking and flooding it out? I dont see or smell any fuel leaks?? I havent run any computer diagnostics, so i should probably do that...

[justy90240sx]

have you checked your injectors or for a vaccum leak like i recomended? did you find anything there?

[aziankingz]

wow i have the same problem as you on my sohc motor.. getting good compression and no vacuum leaks. if you can find the problem that would be great. i am going to see if my friend can change the cat for me to see if that is the culprit.. ill let you know if anything.

[kernan240sx]

I dont think i have a vacuum link, my idle is from 700-800 when car is warm. Injectors dont appear to be leaking? How would i check?

[gtc_240sx]

man .....trust me... it has a vacumm leak, it happen to me too. one day it will run fine and other day it will run as if i have a v8(plump plump plump) sound... check the vacumm line that is near the firewall and the EGR... one of them could be broken, like mine... fix it, and now drives smoothly