2000 Q45a engine skips during idle

[2000Q]

2000 Q45aThe engine skips & almost stalls during idle.I have had the dealer twice replace the air filter & clean jets.No luck - problem comes back within 1 mile after leavingthe dealer. Anyone ever experience similiar?

[maxnix]

Well, first off, there is no 2000 Q45a, nor are there any jets.

Perhaps the dealer cleaned the injectors, did he do so by a rail flush? Usually, dealers just fog the intake path.

How about a little more information, like miles, service history (have you replaced the fuel filter recently?). Skipping at idle is not normal, needless to say. How did the airfilter look?

On a wild shot, you might try running a couple of bottles of ISOheet (not Heet) through your tank to see if you have condensation. If the stumbling is more prevalent on a low tank or after it has been sitting awhile, this would be a good first measure, with the fuel filter second if it has been on more than 12K miles, or if the tank is indeed contaminated.

[PalmerWMD]

2000Q,

Welcome to our little club.:fruit.Common cuilprits often are fuel filters on thses issues as well.If your fuel filter is original it needs to be changed anyway so you might change that and see what happens (its cheap to do too).

Fred...

[2000Q]

2000 Q45 Anniversary EditionDealer cleaned the injectors - standard dealer service, so probably not "rail flush"

56K miles. Problem started last yearwith 40K miles and the dealer never fixed it. Fuel filter has never been replaced, so thanks for the suggestion.I'm surprised the dealer never recommended replacing it.

Dealer replaced the air filter twice in 6 months - May 03 and then again 9K miles later. I never asked to see the filters, they just replaced it twice (and I paid twice).

Dealer also said that the engine stuttering was normal when the heat/air con kicked in (not...). When the engine started to skip, I would shut off the heat/air and it still happened.

Outside temp hot or cold, it has had the same problem for 12 months in all weather. It seems to be worse when I do a lot of short trips - i.e. drive 15 minutes and shut off the car for 1 hour & do the same 2-3 times in one day.

I can also go 3-4 days without it happenning at all. Oother days it's really bad and consistently skips 3-4 times each time I stop at a red light.

I also checked the full tank/low tank idea 2 months ago - doesn't matter.

I have tried over the past 12 months to see what unique situations I was in when it happenned. Conclusion - it just happens when it wants.

I hope it's the fuel filter. ANy other possibilities? The dealer is stumped and wants the car for 2-3 days. I told him I would ask NICO and bring in the printouts for him to try.

The car has 4K left under warranty and if it is something $$, I'm trying to cover it now.

Thanks for your replies - they help a lot!

[PalmerWMD]

200Q I hope our gurus see you post soon.

In the meantime the short trips plus intermittent nature leads me to also consider injectors ( even tho such failures are not as comon in newer Q's).

I am unsure if they did a rail flush or not.

Injectors certainly would a warranty item.

Fred...

[elwesso]

Maybe a few redlines could help!!!

Fortunately you have OBDII... take your car and have the codes scanned..... that will tell quite a bit..

It sounds more like an electrical deal than an actual injector..... If it were an injector it would be terrible, but if its intermittant that leads me to believe its a bad connection... it could be a matter of checking a connection, cleaning it!! Free repairs!

A filter wouldnt cause intermittant bad idle.....

Maybe clean the MAF with brake parts cleaner...

[maxnix]

Do the fuel filter first. ISOHeet is still a good bet as there may be more than one cause. Final (and still maybe necessary due to non-changing of the fuel filter) is a rail flush.

Fuel filter should have been changed at 30K mile service.

I would advise against redlining until the problem is fixed. Watch the dealer like a hawk. He sounds less than competent. Measuring fuel pressure should have been part of the diagnosis.__________________Brian1995 Q45 & Q45t & 2000 Q45

Discover the power of the button!

[elwesso]

Thats true... Do the cheap and easy stuff before you dig into the expensive and no fun stuff!!!

[2000Q]

dropping off the car tomorrow am for a 2 day evaluation. will let you know what they did & how it runs

[2000Q]

All -Thanks for the suggestions. After 2 days at the dealer they replaced the MAF and the fuel filter. The ride home was good. The next day it came back - ahhhh! There's something to be said about the redline comment. The dealer is 30 minutes away - all highway driving. Whe I bring it over there they can never repeat the problem. A couple days later (of mostly city/town driving) the problem comes back. The problem was consistent if I drove the car around town with several short trips and no highway driving. Today I took it out on the highway in 2nd, go up to RPM of 5-6K for approx 1 mile, and the problem went away. I will drive around town again for 3-4 days (no highway) and see if the problem gradually comes back. Bottom line - new MAF and fuel filter did nothing.

[elwesso]

Maybe clogged injectors, redlines help clean them out?

[2000Q]

dealer also said that they did NOT do a rail flush

[elwesso]

Maybe that should be done.. Couldnt hurt anything.....

[2000Q]

What will the rail flush do? This problem has been going on for almost 1 year now. I don't want to do a rail flush and then have the problem come back in 2-3 days. How can I road test it for a problem with the injectors - any ideas? Today's around town driving late in the day brought the problem right back. The high revs helped earlier this AM, but only temporarily - about 30 minutes of around town driving.

[elwesso]

I would say that it may/may not help, but either way its good for the car, and should be done regardless......

The rail flush simply cleans the injectors...

[2000Q]

I thought I also came across a posting where one of the injectors never shut off that might be the problem. How would the car react/feel if this was the problem? Can the dealer test for this? I haven't been too impressed with the OBDII since it's now going back for the fourth time. New air filter twice, new fuel filter, injectors cleaned (no rail flush), new MAF.... Gettin' pretty fustrating....

[VA99Q45]

Here are some good links on the erratic idle:http://home.swipnet.se/e-solutions/Idle ... Tech2.html

Locating the problem is very hard because there are so many parts that can affect the car's idling.

Here is my list from most likely to least likely culprit:

IAC idle air controlcoil pack & plugsColant temp sensorThrottle position sensorFuel pressure regulatorcrank possition sensorEGR valve not closePCV valveReprogram ECMECU harness connectorvacuum leakdirt on fuel systemplugged catalytic converterclogged exhaut systeminjectorMASO2 sensorthrottle cable

[2000Q]

Thanks VA99Q45. I'll take your list of suggestions back to the dealer.

[2000Q]

Going on the assumption that the engine skipped more during local driving, I took backroads to the dealer. I had a tech hook up the portable OBDII unit and we went for a drive. We went about 10 feet when the engine skipped. After 15 minutes of driving and approx 100 skips o fthe engine, the tech narrowed it down to the injectors. Bank 1 column readouts were consistently 100 to 101, which I hear is normal. Bank 2 column readout was consistantly 96, which they tell me means that Bank 2 of injectors is running rich. New injectors on order + other misc parts. I'll update once they install the new injectors.

[Q45tech]

Not unusal for brand new injectors to have a 3-4% variance in flow. Bet the plugs are fouled from no aggressive driving.........lean not rich misfire.

Nice its still under warranty they can replace everything.

[2000Q]

It has started to backfire when I step on the gas from a rollling stop. Gas mileage is probably in the 10mpg range now. It has become almost undriveable with all of the engine skips - almost every 5 seconds at a stop light. On Friday, the dealer told me to "muscle it through the weekend" and bring it in on Monday. I'm taking it in to replace the 4 injectors on Bank 2. Injectors & O rings took 8 days for parts delivery. Dealer wants to keep the car for 3 days. I'm looking forward to posting a positive result when I get the car back.

[elwesso]

We hope to hear something good!!

[2000Q]

Stopped driving the car on Friday. Didn't even start it on Sat or Sunday. I started it on Monday and immediately drove it to the dealer. Of course, the entire way there the engine did not skip once, which verifies the theory that it only happens on numerous, short drives. I should be getting the car back today. Friday undriveable, Monday (after a two day rest) no engine skip. ??????

[VA99Q45]

I am not sure if my erratic idle is fixed or not. But for the last week or so, I have not notied it.

I tried the followings:1. adjust idle screw (2.5 turn from all the way down)2. replaced spark plugs (Q45tech suggested that the plugs may be fouled)3. switch to Texaco gas instead of Exon4. Tried injector cleaner BG44k

I notied when I switch to Texaco gas, it got better. When I changed out the spark plugs, it also got much better. Finally, I tried the BG44k, I have not notied. Knock on wood!

[VA99Q45]

2000Q,

How much does the dealer charged you so far to diagnose this problem? Does your car still have the bumper to bumper warantee or just the power train warantee?

Thanks

[2000Q]

Dealer had the car for 3 days. Replaced 4 fuel injectors on Bank 2 (invoice says Bank 1 - might be a typo), gaskets, O rings, insulator - $832 parts & labor all covered under warranty. Also found failure code P0305 - cylinder #5 misfire. Replaced ignition coil and reset - all OK. New Coil for #5 also covered under warranty. Drove it home from the dealer, so far all OK. I will post a final (hopefully) next week after several days of driving.

[2000Q]

1 month later - no problems, all OK

[Q45tech]

The post 96Q used a different design coil pack [lower cost/lighter], while older models almost never have problems, newer ones do after the first plug change.