Rough Idle after High Speed

[Helmuth48]

OK....this has got me.....car runs great around town...but when you hit the freeway and run it 60- 70 mph for 30mins or more...when you come off ramp stop...it want to die. Only way to keep it running is to power brake it and increase the idle speed.
Shut it off...wait 20 minutes.....everything back to normal...

I have check the computer....No error codes...

Any suggestions...thanks,

[hungtdao]

It sounds like you will ignition coil problem if your car is in year 97-00. If it is, there are some posts in past tell you about the website of how to read the flash code from your "Service Engine Soon" light then find out what ignition coil number needs to be replaced.

[Helmuth48]

I forgot to add this is early model...1985....
I have checked the computer...no codes!!!
It has only one coil.....I just replaced the MAF for another problem....this issue keeps coming back!!

[hungtdao]

Some early model does not provide as many codes as the later models. If engine is rough, tt sounds like something is misfire.

[Helmuth48]

It seem more like a rich fuel mixture than a miss fire.....I am going to check the fuel pressure regulator and them maybe switch out the air regulator...I have a parts car I bought for $200.00 that ran great...but has a blow head gasket....
Thanks for the help....

[toli]

had the same problem. turned out one of the injectors was bad. good luck

[toli]

its me again.... i had the same problem .... i took it to nissan for a check up ........ couldnt figure out the problem because at the time it ran good. so i took the car on the high way for about five minutes and dogged it and quickly returned to nissan. to make a long story short.... one of the injectors wanst working. good luck.