Hey all. Just got a 1998 neon dohc. I have something going on and I need your help. When you first start it it fires right up, shudders heavily then idles good for 20-30 seconds-then it starts pulsing/surging about every half second to a second. I changed plugs, wires, air filter, new pcv, throttle body is clean, pulled injectors and cleaned rail and injectors but, alas the problem remains. Also...for being more hp than a sohc my buddy kicked my butt in his. It only does this at idle, cruises smooth, shifts great but, lacks good power and it is driving me nuts.. Please help. Thanx[sm=headbang.gif]

 

Checked your TPS?

DOHC's were overrated from the factory. Do you have an ATX or MTX and what does your buddy have?

 

Both atx. Our other friend has a 97' atx dohc and is faster than we are.I'd deal with the slowness if I could get the surging fixed. I'll look at the tps then.

 

Nope...TPS checked out good. Even had the parts house check it. Took the throttle body off and cleaned it 100% and the IAC also. No change what so ever. It sucks because it throws NO codes.

 

Ok so heres what happend when it did that for me. First good idea/bad idea, I put RICE (YES RICE) into the intake, (cleans the pistons like a glass bead but without the glass =D ) I think something happened witht he IAC or the TPS. They check out fine voltage wise, but mechanicly one of the two wasnt doing the job. I think it was the TPS. it has a spring on it and a little valve opens and closes in the trottle body. Well we dabbled with this, and it stopped doing that. I think a piece of rice got stuck somewhere in there and jammed it open. Check the functionallity of both parts on the trottle body. Who knows mabye its gremlins =D Good luck chap!

 

Ok...I need professional help here. I was spraying carb cleaner around the head and vac lines...When I got to the EGR is smoothed out. stopped spraying and it did it again..sprayed and smoothed out. Great I found a vac. leak. I splurged because I was so elated it worked that I got the whole egr and solenoid kit. Put it on ..cranked right up (it always did cold) idled great....took it for a ride...great idle. Came home and turned the car off. cranked it right back up and same crap. It does it when it's warmed up......WTF....

 

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