95 Q45 new plugs or flush?

[dcook]

:help My95 Q45 was running fine until SOMEBODY went over 90 on the interstate....then it starting missing a little. It has 133,000 miles on it so I'm thinking new spark plugs, and the Nissan dealer mechanic here (although they RARELY work on these cars) suggested some sort of engine flush for $99. Does this sound right to you? I replaced the fuel pump and filter about 15,000 miles ago. Thanks for your help.. dcook

[DAEDALUS]

If the engine is missing a cylinder an engine flush won't bring it back. An injector flush might, but I don't think injectors are likely to get varnished up while running. Don't blame the "over 90" run...something was probably on its way out already. Over 90 isn't exactly wide-open throttle, and nowhere near the car's limits.Could be the plugs but it could also be an injector, or even a coil. No way to know without some diagnosis.

[maxnix]

Well, if you didn't clean the tank and the fuel lines when you did the fuel pump replacement, you might have some detritus obstructing the fuel filter. It is past due time to change it, so do that first. Next try a can of BG44k. A rail flush could be your next step, but further diagnosis (a consult read out) would be best.

Where are you located, how many miles on the car, what miantenance has been performed recently.

Welcome to the world's best resource for the Q45 of any year.

[Falkdesigns]

I drive 80-85 in the left lane (flow of traffic) every day coming to work / going home, and hit 90-100 whenever someones going under 80 in the left lane and I have to pass on the right (God forbid that someone actually move over when you flash your lights, never happens here).

It's not going over 90 that caused the problem, but I'd go through the steps that Maxnix suggested.

[dcook]

I live in Mississippi. I bought this car with 80,000 miles on it and now it has 133,000. We've done the fuel pump and filter (I know it's time to redo that), new tires and rear struts, a transmission flush, and changed the oil. It has a quick little tapping somewhere up front (which started the first time I got the oil changed) and now, just since this other problem started, it is getting harder to start....never had to touch the gas before but now you really do. Other than that, I love this car....mostly because people I don't even know come up and admire it, even ask if it's for sale. They can't tell that it's almost ten years old. dcook

[maxnix]

Did you do the 120K (60K) service? How about cleaning the intake passages from the MAF back and the the EGR and IAC valves?

[elwesso]

If the 120k service hasnt been done then you need new plugs.....

When my Q was under the ownership of the previous owner, he said he had a hard start condition with the fuel filter... About 1000 miles later the pump and controller failed, thank diety I didnt have to deal with that!!!!

new OEM filter is $10, its worht the gamble IMHO.....