Help! Car runs rough after 10-20 minutes and black smoke than stops.

[mixcat]

Hello guys!

Looking for a little help here.. I have a 1995 Q45 that runs great for a little and than starts sputtering and I get black smoke like the motor is running super rich. You will feel the car loose power and if I let it sit idle it will conk out. This issue seems to come and go. It will run perfect for a while than start up. I have already ran some Chevorn Techron threw it thinking bad gass and this might clean it, I only run premium and this is my 3rd tank and seems to be getting worse. I brought it down to Discount Auto and the machine they use to pull codes from the computer didnt fit this car. So I was not able to pull a code. My thought are bad wire or plug? Or Oxigen Senser? Any ideas or a starting place to test?

Thanks everyone!-Petehttp://www.mixcat.com

[chinaonnitrous]

uhhh....

white smoke=coolantblue smoke= oil

black smoke= *boom*?

[mixcat]

Again it loads up for a while than stops and runs perfect.. Seems to happen after I drive for a while.. I had a 100+ mile trip yesterday and it started toward the end of the trip but cleared up by the time I got home.

-Pete

[Q45denver]

Are you getting a check engine light? If so, you can pull the codes yourself.

[elwesso]

Im leaning toward a MAF related problem.....

[Jesda]

Does it do anything at stoplights or while driving?

Its either a leaking injector flooding the engine (less likely) or a bad MAF like Wes said (much more likely). 95-96 Q45s use the same MAF. Order a used one from car-part.com ($30-$70) to see if it resolves the issue.

[mixcat]

No check engine lights... I cleaned out the Throttle body and changed out the gas filter and now its running a lot better. I ran it for a couple miles but before long it did sputter for about 3-5 sec. but snapped back really quick.. Seem to be a lot better it will not stall @ a light now during these sputter spells. I think you guys are right about the MAF.. Is there another way for me to get the car to throw codes to read?

Thanks for all your help!-Petehttp://www.mixcat.com

[elwesso]

NO theres no other way to read the codes..... really.

Dont expect the car to tell you whats wrong!!! Id start by cleaning the MAF.. see if that does anything..

[mixcat]

Do I clean that like I cleaned the throttle body? Same carb cleaner? I will try that tomorrow. Thanks again,-Pete

[elwesso]

Yep.. Check Q45.org for more information if you need it... just be sure its pretty dry when you put it back on the car... (let it dry for at least 5-10 mins).. Also, dont douche it with cleaner, just gentleness.

[mixcat]

Nice... Going to the store and getting the electronic cleaner now.. If it was still light out I would be out there right now... I need to take some pics of the car and post it up.. Its comming along very nicely.Thanks for everyones help and enjoy the weekend,-Petehttp://www.mixcat.com

[mixcat]

Hey made it to the store OK and went to leave and started the car up I had issues keeping it running.. ITs loading up big time and giving me a lot of black smoke.. I had to double peddle it to get it to get on the road but in 2 minutes it when away again.. I did pick up the electronic cleaner and will try that out in the morning.. Discount didnt have the mass air flow, I figured I would ask...;o) So if that cleaner dont work it seems I have to order one. Is there anything else it could be that I should look @ tomorrow?Or a way to make sure its the MAF.. Can I jump it out or something to see if it makes a difference? not sure it thats even poss but thought I would ask...Thanks all,-Pete

[elwesso]

First make sure its not the connector..... Next time it starts running goofy wiggle the MAF connector and see if that changes anything.

[mixcat]

I think your right with the MAF connector or unit... It was running bad and I got out fast before it conked out on me and shuck the connector and it smoothed out for a little than started bogging down again.. I really shuck it harder and it ran well and I ran it around the parking lot and it got bad again.. I took off the connector and it ran higher idle but ran fine.. No black smoke, I let it sit for a sec than put it back on and it shut right off. I re-stared it and it was smooth..so we are looking @ a connector or MAF im thinking.. Now the question will be does the cleaner fix it tomorrow and if not the fastest way to get a MAF so I can use this car. Im going to clean the connectors on the MAF well and it looks like the clip for the connector is cracked so I might replace that if I can find that clip and solder a new one in.. So I am safe to assume the MAF if its not working will produce lots of black smoke and loading up effect?Thanks,-Pete

[goody90q45]

My 6 month run of having my Q run great has come to an end- I am also having what I think are MAF problems. She started idling rough a couple of days ago when the fuel tank got to about 1/8 full (I never let it get below 1/4), but no black smoke. Filled it up and the rough idle went away (along with the check engine light), but now it has returned full time. I cleaned the throttle body and MAF with no improvement. Wiggled the connector with no change. Haven't pulled the codes yet, I'll do it in the morning.

If it is the MAF, is my '94 interchangeable with an older Q (there's an abandoned one at work)? I looked it up on Joe's site and they are listed at $386. DO NICO members get it cheaper than this? I don't mind buying a new one but I need to make sure this is the problem before putting out the big $$$. Of course this is all speculation until I pull the ECU codes.

Since I personally know no other Q owners locally, are there any members in the Sacramento area who would give me 20 minutes of their time and let me swap in their MAF to verify the problem?

[Q451990]

Joe's site is the discounted price...

Heath

[mixcat]

MAF was the issue!! I used the Electronic Cleaner as outlined and it seems to be running a heck of a lot better! No sputtering and seems to have more pep.. I also ordered an air filter as it looks like it can use one.. Thanks for your help on this one Elwesso your the man!-Pete