PelicanParts.com

ebaker had a good DIY for coils/plugs on the tt:
https://rennlist.com/forums/996-1998...g-r-and-r.html

judd944

I drove my car today and had my tech put it on the computer. the cams move together and he does not see any issue there. he suggested removing the spark plugs and checking to see if I burned them and enlarged the gap. he thinks when I get into boost it blows out the spark causing a misfire. I have only been seeing the misfire regisred in Cylinders 1-3 today.
There was no misfires on the engine when revving it out of gear. The engine has to be loaded to have the CE light flash. Thank you for the DIY link as I will be doing that later this month!

turbo4 me

Check your MAF. Unplug it and drive the hell out of the car. If that solves your problem, replace the MAF.

Macster

IIRC the engine has a tune, you've been running discount gasoline, and doing some tracking.

I'd agree about removing the plugs and having a good look at them but I'd not reuse them. I'd replace them just on general principles.

While a stock engine -- based on my experience -- gets good miles out of its plugs/coils and O2 sensors a tuned engine, one pushed hard, and fed discount gasoline, may not get as good of miles. As with the plugs the sensors are subjected to a harsher service life and this has to result in their having a shorter service life.

So what Kevin advises regarding plugs/coils and sensors has some validity.

Kevinmacd

If you change out your plugs, change out the fuel filter also.

Macster

Good point. Based on my time with my Boxster I've fallen out of the fuel filter service habit (no serviceable fuel filter in the Boxster), but the Turbo has one, a small one and it needs periodic replacement.

Which reminds me.. I can't recall when my Turbof's fuel filter was last done. Oh oh... Probably better have the service manager look that up. Getting ready to head out on a two week road trip and I want the car in tip tip shape.

judd944

Great points guys. I am going to drive it home and start to remove the rear bumper next week. I will plan on doing all the spark plugs. I called the old dealer in Cleveland that had the car from 04-09 and the last time plugs were done it had 18.9k on it. just over 42k now so it is time. none of the dealers put coils on it so it is the old 996 part number 42k mile units that are in there.
I am on the fence about replacing those as I will be much faster getting in there the second time should I need to in a year or so.

I did find out that the car had the lifters replaced due to them sticking at 24k. it was an engine out procedure with 55 hours of labor billed !!!

32krazy!

yes you reach the coil pack from underneath. # 6 is the pass side farthest forward plug


i had spark plug blowout issues with mine. used ngk iridium plugs and no change. went to denso double platinum and gapped to .24 and issues are now gone

judd944

got 30 min to work on the car tonight and I removed the bumperettes and rear taillights. next week I plan on taking the car to a friends and putting it on his lift to do the rest.
Got a much later start on the project than I had hoped ! I did buy a fuel filter as well as six plugs. going to wait on the coils.

32krazy!

coils have to be removed to get to the plugs. may as well wait until you have the coils and only bleed once! chances are if you have decent miles on them or age like mine were original 10 yrs old they need replacing anyway

Danyol

Good luck.

I'd be interested to know whether your plugs are loose as well?

Thanks

judd944

I would be shocked if it was the plugs as I was getting misfires on all six cylinders at once. no way they would all fail like that.
I will put the new plugs in then drive it for a few miles to see how it operates. if everything is good I will put the bumper and taillights back in.

Can I drive the car without intercoolers attached or is that asking for trouble? I will not let the car get very hot.

Macster

Put the car back together fully and correctly before any test drive.

Danyol

No, the intercoolers are between the turbos and engine under positive pressure. The ECU will be throwing all kinds of codes, lighting up the dash like a christmas tree. At a minimum the intercoolers go back, the time you'll be saving is the bumper and tail lights, maybe 20 minutes work for 2 guys on a lift. On this one occassion I'll agree with Mac :-)

raineycd

Misfire on all 6, I would look at the MAF or a vac leak - do a boost leak test for sure if you haven't.