Took my car to the delaer the other day to have them check out a hesitation when accelerating. Usually occured at around 55-60 MPH, when slightly pressing the pedal. They told me my transmission needed to be replaced under warranty. After picking up the car with a "new" transmission, the problem was worse, only at 50 MPH. Took it back and they said it had several missfires but they couldn't troubleshoot further until they replaced the injectors and it would cost $780.00 P&L. I replaced them myself for $210.00 and three beers. Through all of this my CEL has not come on once. I purchased two coil packs from the dealer and played musical coiuls, trying to identify a bad coil pack, with no luck. Plugs changed and also tried resetting the ECU twice, including letting it idle for 15 Min. Any help anyone can offer would be greatly appreciated. Where should I look next?

 

if you had a bad coil pack it would misfire during idle and you certianly would know. if you said your CEL has not come on at all then i really dont think your misfiring. because the slightest misfire will throw a CEL.

 

Unfortunately, the car does missfire at idle. I can hear it via the exhaust and feel the slight shake. Also visually verified by watching the engine shake. Any help would be appreciated.

 

Definately sounds like a coil pack to me. How many miles are you at? I suggest changing all six. Might be a bit expensive but its worth avoiding the hassle of each coil going one by one over time.

 

I took the car back to the dealer and they insist it is the fuel injectors, claiming that it was caused by mu use of Denso plugs. I called their bullshit when they installed a "fresh" set and the problem still existed. Here's a good one, when I changed the plugs two days prior, I put the old Bosche plugs in the trunk. When they called to ask if they could change the plugs they stated that they found 5 Denso's and 1 Bosche plug in the car. When I went to the dealer I went right to the bay where my car was parked, opened the trunk and there were only 5 Bosche in the trunk. I have 6 empty Denso boxes, so I asked them if they thought I was fucking stupid, unable to count past five or ate one of the Denso's. I'm so tired of the Stealership. If you are in Florida, stay away from Regal. There's nothing regal about them.

 

Go to AutoZone and have them read the codes. Then let us know what they are and hopefully we can help you out.

 

Same problem here--a minor misfire at about 55--this with new plugs, dealer checking the transmission and determining no problem, etc. We have just decided to live with it.

 

There is a way to test the coil packs, without removing them.


Tools needed:

Hands,
Multimeter,


If you remove the connectors from one of your coilpacks, their should be 3 exposed terminals, I do not remember if its 1-2 or 2-3 or 1-3 that you are supposed to test (try each one), but it should yeild a resistance (depending on the coiltype) between 1 - 1200Ohms, these should be the same between each coilpack, however if one of them is different, I believe that coilpack could be faulty.

I.e

Coilpack #1 -- 1200ohms
Coilpack #2 -- 1200ohms
Coilpack #3 -- 437 ohms <---assume faulty


good luck!

 

The Bosch plugs are not the greatest thing for our cars and tend to foul and allow carbon buildup in the system due to different voltage requirements than Denso or NGK- the designated approved plugs for the car

A can of Seafoam run into the gas tank to clean to the injectors themselves and a bunch- like a full can treatment to the maifold vac line to clean all the junk off the valves and pistons, should help you a lot and may cure problem- has never hurt anyone to do it
See gen 2 thread Seafoamed the ol TL for 10 page pics description of this 30 minute 8 buck a can fix-
Same product used in dealer fuel injector servce for 99-149$

 

May as well try to check your battery voltage without the car running.

 

I have had same problem; 2000 TL s/ 210K. replaced injectors, tried 2 different sets of plugs, cleaned egr, replaced evap system , replaced fuel pressure sensor, replaced TCS, MAP, all manifold gaskets..symptoms remain. No codes showing up. I am going to check coil packs..but I don't know why this would occur only between 55 and 60MPH.
Just my FYI..the only reliable way to check codes on these vehicles is with either 1. dealer 2.Use the Snap-On diagnostic tool ($3000)..I borrowed one.
All the other OPM readers are not worth the effor.