1997 Q45 is acting up. Likely causes needed

[BigP]

My son's 97 Q with 151,000 is losing power intermittently, the check engine light comes on at times, and go's back off unpredictably. The plugs were changed by a dealer about 6 years ago at 50,000 miles. The car has been well maintained and fed 93 octane. He says it spits and sputters sometimes and then seems to revert to running well others. The idle RPM is sometimes down below 500. Does it need a tune-up? Is this indicative of some computer malfunction? Fuel injectors? New spark plugs in order?

Anybody know of the likely causes.

thanks, Mike

[paranoidjack]

FGY33's are known for bad coilpacks, but that is more intermittent. Most don't complain of it stalling the engine.

I'd say to inspect and clean your MAF sensor (just past your air filter inside the black tubing), and also to ensure battery connections are clean and tight.

Have the alternator tested (and battery as well) at Autozone or a local auto center. Have them read your codes as well (even if CEL is off) for additional information.

That will all cost you $0! (perhaps $5 for a can of MAF cleaner at NAPA)

Also Mike, our cars are very picky about which spark plugs to use and most everyone here will run only with stock NGK plugs.

All of your parts should be purchased from Infiniti dealers - use only OEM parts for most components. We are sponsored by Infiniti of Scottsdale, and you can buy parts from them at http://www.infinitipartsusa.com

[BigP]

Thanks. Will suggest he check that out and we will report back. Beautiful white 2000Q you have. I just sold a white 99Q. I think I'll regret it!

[maxnix]

Cleaning the MAF risks more damage than benefit unless air intake filter change intervals have been abused.

How a bout a maintenance history? When was the fule filter last changed? How often previously? When was the TB and IAC and EGR valves last cleaned?

Give us some information to help you.

Alternator and battery are good places to start as if one or both are faltering, nothing else electronic can be easily verified.

[paranoidjack]

Cleaning the MAF risks more damage than benefit unless air intake filter change intervals have been abused.

Oh, come on, even a MAF sensor needs fun every now and then

[maxnix]

Yes, but unless it is truly oiled, much better not to touch it.

[miata007]

Best thing to do is to get a OBDII scanner and read the code since you have check engine light on.

The Y33 is prone to all kinds of hiccups, shake, mis-fire problem.

007

[BigP]

I'll report back with more maintenance history and what we learn. The car pretty much had the prescribed maintenance at the prescribed intervals. I'm sure things like fuel filter, belts, and the like were all done as prescribed. The oil is changed every 3000. thanks, Mike

[maxnix]

Fuel, intake and cabin filters require annual changes to work. More often on fuel if in ethanol area.

[bullittandy]

Yes, but unless it is truly oiled, much better not to touch it.

You don't touch it-you spray it with MAF cleaner.

[BadQ45t]

Well the plugs are 100k old, these are NOT 100k plugs, they were designed to be changed very 60k, so i'd take it in for a full tune-up including the plugs, and while they have everything taken apart I'd do new knock senors at the same time. Also as they said fuel filter etc should all be changed too.

[miata007]

To save money, I would still use an engine scanner to know what the complain is about. Atleast have the mechanic check it.

I don't think spark plugs and KS will cause the issues you are facing.Most likely is the coils if your car is over 100K and has not been replaced before.

007