Crackership

Ok, so, unless I'm retarded, that goes in the "nice to have, but not imperative" category?

I don't know how many curse words I've invented in the process of putting the cap back on... I HATE that bottom screw-thingy!

But yeah, I think the cap/rotor/coil thing will have to happen in the very near future. Ever since I looked at them last, I haven't been able to completely dismiss them as potential sources of my problems.

As for electrical cleaner, I have a can of this stuff:


But I'm hesitant to use it on the MAF... and only because it doesn't say "MAF Cleaner" on it... what do you think?

As for backfires between shifts at WOT, I'm not so sure... I don't get a lot of chances (read un-patrolled roads) to do a lot of hard driving I'll have to see if I can get away with a good pull tomorrow and get back to you.

I firmly believe that there are no dumb questions... but people push it sometimes. Once, when I worked at an IT Helpdesk, a lady handed a corded mouse and told that the batteries were dead and that she'd really rather have one with a shorter antenna...

No, that's a good point. I checked it when I had the intake manifold off to replace the vacuum hoses/lines, but there is always a possibility it got bumped just a bit or something during the re-installation of the manifold. I'll check it out. Thanks.

schip43

I helped oil filter guy without giving him grife but still on this board that was a new one! I'd be hesitant to use that. I bought some throttle body spray at the auto store or hell Goggle MAf cleaner and see what shows up!

Crackership

yeah, I'll grab some MAF cleaner tomorrow... I didn't today, because I knew I had a can of it on the shelf... and I was right, I had a can... without anything in it... on the shelf.

I just have that other stuff, and I just wanted to hear someone other than the voice in my head to tell me that it wasn't a good idea. Thanks.

running_cold924

x2 on tps check and clean your grounds...

Crackership

ok, so, I cleaned my MAF, checked my TPS adjustment and inspected, cleaned and dielectric greased my grounds. The TPS was perfectly adjusted, so I guess testing for function is all that's left there. The grounds looked fine, but I went though them anyway. After cleaning/greasing my grounds, I metered several spots between the battery, engine, and chassis and there is no more than 1/2 ohm between any two points. The MAF was fairly dirty though.

So, now that it's cleaned, my AFR's are better... but still not exactly where I think they should be. They still wander around a bit at warm idle, and it still goes rich at very light throttle, and still backfires sometimes on shifts during normal driving. In the time I was driving it, the hesitation on WOT seems to be gone, but I can't say for sure, because it was never consistent before, just occasional.

As for the earlier question as to whether or not it backfires on WOT shifts... No, not that I can tell. I did several WOT pulls to redline and then WOT immediately after the shift, and it never backfired.

So, I guess the next step is to get the cap/rotor/coil replaced...

Any other thoughts?

running_cold924

same here man. mine do just that. i have noticed after these hot days and the sun goes down, the moisture in the air makes for some perfect a/f ratios and the car really comes alive. on hot humid days, forget it. they can do some crazy stuff...i mean it runs good, but not like it does at night.

i did gap my ngk plugs at .026 and replaced the coil with a MSD unit. nice magnacore wires too.

Bri Bro

Here is what I would do next. Get a SMT6 or SMT8 or equivalent tuning device and start recording what is going on throughout the RPM range vs AFR and boost. Without that info, everyone is guessing.

jmj951

I have an original coil as well, and have been thinking I probably need this upgrade for the track. For those that have installed an MSD coil, could you please provide the part number you used? Will the same part work for most all 951's, or are there multiple considerations in selecting the right coil? Mine is a mostly stock OEM 2.5L 26/6, with Vitesse MAF/chip, 3bar FPR, 3" exhaust from the downpipe back.

EDIT: Forget the MSD Coil upgrade. I've been doing research and have yet to find any evidence that just upgrading the coil is any better than a properly functioning stock coil (on a standard engine like mine with all other ignition parts stock). Also, there are some considerations I don't want to deal with - such as mounting (the MSD coil is smaller than stock), the ballast resistor (many say it's not needed, but then you run the risk of burning out the driver in the DME), and possibly burning up the rotor prematurely. To me, it seems like an ignition upgrade is all-or-nothing - convert to a good wasted spark setup or just keep your stock ignition components in good working order.

Interesting thread though, because I have a CEP fuel rail with adjustable regulator and gauge sitting in a box ready to install - just won't have time to install this for quite a while. I haven't thought about feeding the fuel pressure to a gauge inside the car, but after reading this it's got me thinking that I'd really like to do that and it looks like I should now that I'll have a non-stock part managing my FP.

toddk911

Honestly, it sounds like you have normal a/f blips here and there and no real worries. Especially no worries beyond cap, rotor and maybe coil.

And yes, from warm day to cool day these cars, like most turbos, are night and day.

I remember a quote from a Porsche race driver in the 70's saying in regards to turbo for the track "even when the sun peaks out from the clouds, we need to change the set up" lol