Running super rich...makes you cry

[one ton garage]

Was helping a friend work on his Q the other day... and would like to ask you guys for some help in diagnosing a problem since neither of us have gotten a hold of an FSM yet. The major symptoms:- runs extraordinarily rich... it straight up dumps liquid fuel out the exhaust and blows a very nice smoke screen.- start up idle is VERY nice and smooth, but once warmed up, it's game over. The idle is still not bad when warm, but the car can not really be driven well.

Interesting anomalies:- even when dumping fuel once warmed up, the engine can idle and rev fine w/o a load. This leads me to believe that the problem is isolated to just one to two cyls at most. We had gone through the ignition system and replaced spark plugs and checked all coil packs, ignitors, and ign harnesses for functionality a while ago, before this extreme rich condition got to this point, so the ignition system works... but I suppose a tell-tale sign to see which cyls might be affected would be to pull all the plugs and read them now (though we are laaaazy).- I did notice a mugh higher pulse rate in at least one of the injectors at idle, and with a slight rev... this leads me to believe that the culprit may be an inj that is just dumping fuel.

Questions:Before delving further into our tedious troubleshooting methodology sans FSM, are there any common problems you guys tend to encounter that can lead to the same problem we are experiencing with my friend's car? Is this condition something that happens often, and/or maybe there's something more wicked hiding behind the curtain (considering the vast amounts of electronic items in this car) that we'd never be able to find out just through normal diagnosing?

Oh yah, shoot, and while I'm already asking about fuel delivery issues, is it possible that a fuel pump-related problem might cause some hesitation during tip-in? I'd really like to go through the whole fuel system in my Q and convert the pump to straight voltage and eliminate any-and all-dampers that may be present in the delivery lines if that would help (unless this is a highly unrecommended route to take with these cars)...? Thanks in advance for any help you guys can provide with either of these problems...

[911/Q45]

Bad injectors are very common, especially on CA gas. I just replaced all of mine. Do not recommend bypassing any features of the stock fuel system. It's a very integrated car and you'll be chasing your tail if you change something like that. There are some good troubleshooting techniques available through the FSM and by searching this site for both electrical failure and leaking of the injectors.

[Rex]

Smoe great info can be found in the Infiniti Online Mechanic forum about injectors, but I'll saw I think the "injector" issue is limited to the 93 and earlier due to the pitle or something like that.

Year and mileage as well as what maintenance has been done (and hasn't) will be helpful.

[HeavyDuty]

My 91 was doing a similar thing when I bought it. I cleaned the contacts on the MAF connector & ran an auxilliary ground to an existing ground on the inside of the driver's side strut tower from the harness side of the MAF connector.

My car ran horribly with a bad ground...I'll never forget these two a$$holes in a Jetta screaming FIRE!! FIRE!! as I limped it home from where I bought it.......praying the whole way.

[DAEDALUS]

If not an injector, suspect an injector oring.

[maxnix]

I am glad you said that because I was thinking that. I have not experienced that failure mode, though.

[AZhitman]

If not an injector, suspect an injector oring.

That's what they thought MINE was. Not sure where my NOVEL of a post was, but here's the Cliff's Notes -

Sucked #5 intake valve $3K+ to repair no one has ever seen it happen before hope this isn't your experience...

[JoshIsSciFi]

I have to say, the absolute best thing ever, was on my cavalier, I had dual exhaust from cat back, well, where the cat was SUPPOSED to be, straight pipes back from a y there, and I was shooting 4ft flames out both tips on a regular basis.... was awesome when I had a riced out fool in a civic behind me revving....

[one ton garage]

It's very interesting that I've always heard so many horror stories about the injectors being a major pita in the Qs.. when they use the same injectors as in the SR20DET motors, and I've never really come across a bad one in those applications before. Although, there are sometimes issues with the o-rings there also... so that might be a common failure point.

Hmmm, it does seem like everything points at the injectors being the culprit in the case of my friend's Q, so we'll probably try and tackle that this weekend, and hopefully we can get his car back on the road!

[maxnix]

It's very interesting that I've always heard so many horror stories about the injectors being a major pita in the Qs..

They are not at all, but CA gasoline is! So is not changing fuel filters regularly or cleaning the tank when the pump is replaced.
Modified by maxnix at 10:36 PM 3/26/2005

[one ton garage]

My friend made an interesting video clip of the awesome smoking the other day:http://www.buckaloose.com/q45_smoking.aviNow that the stance is mostly done, I think it's definitely time to get back to working on that engine!

[maxnix]

OK, besides the sound track, what's wrong with this picture?

Maybe the thousands spent on wrecking the suspension rather than maintaining the car?

Naw, that wouldnt be cool, would it? Who wants a car that's reliable, fast and drivable?

Hand me a tissue, please.

[DAEDALUS]

AAaahhhh! Quit running the engine! With that much fuel coming out of it, whichever cylinder is leaking has essentially zero lubrication. The oil is probably all thinned out too. Pull the plugs. Find the bad cylinder. Fix the injector. Hope the compression isn't off by too much. Also hope it doesn't hyrdolock before you can fix it.

[one ton garage]

OK, besides the sound track, what's wrong with this picture?

Maybe the thousands spent on wrecking the suspension rather than maintaining the car?

Naw, that wouldnt be cool, would it? Who wants a car that reliable, fast and drivable?

>HAHAHA< I like how you obviously have an overt enmity towards my posts and modifications. I will remember that. Anyway, when my friend bought the vehicle, it was running fine, so he had acquired parts for it prior to the engine going south. Also, since he has other cars, he did not use the Q as a daily, and working on it was not a priority. Think of it as a classic car... you buy one not expecting it to be perfect, and are more than willing to work on it as a "PROJECT CAR" since it's not your daily driver and your livelihood does not depend on the car reliably taking you to work every day. As such, he continued to work on the getting the parts he already had on to the car just to get them on there, and it's not like the engine will be neglected; it's just the next step. So please open your eyes and your mind to those facts. thank you come again

DAED: You're very right... it is highly possible that the rings have been washed out, and the car is not driven at the moment as we need to go through it and make it nice and happy again now that time is avl....

[DAEDALUS]

Just FYI I had a leaky injector once, a lot of smoke (but no liquid fuel that I was aware of). I put less than 50 miles on the car before fixing it, but that cylinder now measures 10 or 15 psi lower than the other 7. Can't remember the exact number, but it was a huge drop below standard deviaton.

[elwesso]

I think if I had injectors spray gas on the exhaust valves my car would still run better......

HOLY JEBUS.. Thats a nice video, I was ROLLING!!

I should give you a cookie for thta car to still run...

Start saving up for new pre-cats and cats, im surprised that the exhaust still has some flow to it...

That makes me cry there..... That car should be cremated and be put out of its misery....



Brian put it the best... All that money on the suspension "work" (butchering) and no work on upkeep..

[elwesso]

Look at the bright side, running like that you will NEVER have to worry about preignition.....

[maxnix]

Look at the bright side, running like that you will NEVER have to worry about preignition.....

Well, it could be the first Q45 with an afterburner.

[elwesso]

LOL!! Ill hook him up with 2 spark plugs and we'll get that thing to shoot flames... How cool would that be...

obviously not as cool as the suspension.....

[one ton garage]

I'm tempted to stick a pilot light made from an extended bbq lighter in the tailpipe... but that might not be a good idea. Judging from reactions, it'll be very fun to go about "reviving" this motor...

[maxnix]

It would keep the tailgaters away!

[azskygod]

Oh man, you guys are just cracking me up tonight! WTF is up with that video??? Nice music... It took me 10 minutes to stop laughing. Whoever spliced together that AVI is an absolute comedy GENIUS!

Too bad about the car. You really should get that fixed. Thanks for the laugh though.

AZSKYGOD