aowolf

I have a 99 with 125k. In the last few days the tip car has felt a bit "lurchey" Its shifting very quickly like the car is stuck in its sportiest mode. The problem first started when I really got on the power and the car suddenly felt like it dropped out of gear and lost some momentum only to pick back up a second later. No tip warning lights or error modes. I did get a P0102 code today, but I Ive had to replace a MAF before and I feel like this is a different/unrelated issue.

Macster

Maybe. In some cases -- sorry I can't state for sure in this case -- but a MAF acting up can cause trouble in seemingly unrelated areas, like the Tip. (ABS and stabiity control are other areas.)

The MAF signals are used to provide critical info to the Tip (its controller) and if the MAF is acting up the critical info almost certainly will be wrong this wrong info could explain the Tip's behavior.

In cases where the MAF is suspected one 'trick' is to disconnect the MAF at the wiring harness and clear the error codes even though there aren't any to reset the long term fuel trims and other learned data back their defaults then drive the car and see if the symptoms reappear with the MAF out of the picture.

Worth a shot. Because at 125K the Tip may be just wearing out. I hate to say it but...it could be. But it is premature to think about Tip rebuild/replacement.

If the MAF idea proves a bust and if the Tip is still suspect a Tip fluid/filter service might resurrect the Tip.

Since the Tip is acting up anyway it might be worth a fluid/filter service just to see.

Sincerely,

Macster.

Dale_K

I've noticed my Tip seems to smooth out and act more relaxed after a battery disconnect. I did quite a bit of battery disconnecting while running down some problems that eventually required a new MAF sensor. Each time the Tip worked nice a smooth but eventually became more frantic as a few miles built up.

About a month ago I had a major vacuum leak fixed on the brake booster hose. Ever since the Tip has had the nice smooth, non-frantic operation. Based on total guesswork I think the Tip is sensitive to things that affect A/F ratio and therefore throttle action. I can't prove it but that's the way my car acts.

You'd think if Tip suddenly became low on fluid you would see a spot on the ground but maybe if the car has a slow leak it eventully reached a point where it affected operation. In other words, you probably want to check the fluid level, if just for the peace of mind.

I'd disconnect the battery and see if that made a difference and whether the code comes back. Fix the stuff related to the code and see what that does for the tranny operatioin.

aowolf

Thanks for the replies Gentlemen, I'm going to play around with the MAF today today. The only error code Ive gotten is far the intake temp sensor on the MAF. My MAF is a el-chepo ebay one that actually shipped without this sensor (They refunded me the price and I got to keep the part) I was able to solder on the temp sensor my from all MAF and all was well (live data was the same as with a working factory MAF). But before I did that I had the car for a few days with a working MAF and no air temp sensor...and I never had any shifting issues. Also I didn't get any check engine light until yesterday but the Tip issues are at least a week old and seem to be getting worse.

I do have another question: I've heard some horror stories about changing the filters and fluid in a Tip. Something about a seal that fails during the fluid change causing an pump to fail killing the Tip. Has anyone heard of this?

Dale_K

I've actually got all the stuff to do a Tip service but I'm afraid to touch it for fear it make things worse. I haven't heard about any specific part that gets messed up during the work. I posted a thread with the same question elsewhere and the replies basically said you couldn't draw much conclusions from other folks troubles after a Tip service. So many people only do the service as a last resort prayer when they start having trouble that you can't actually attribute their problems to the Tip work because they most likely were on their last legs anyway.

But I would say checking the fluid level is in a different category. You want to correct that if it's low. I'm waiting on the mailman right now because the special 17mm hex key is supposed to arrive from Pelican. It's only $5.

My Tip seems to like the hot weather, at least up to the point that it called for the coolant control valve through the vacuum circuit. The coolant valve had a big vacuum leak but you didn't know it until the hot weather and the computer activated the solenoid valve controlling the vacuum line. A guy in Shanghai, China actually diagnosed that one for me after I described the symptoms on a Boxster forum.

You could try disconnecting the MAF and driving the car. If the Tip worked OK it would take a load off your mind. I can say my car improved a bunch when I put a MAF in. I had crazy numbers in the Durametric fuel adaptation but no actual MAF codes per se. Everything went to normal with the new MAF. It was $275 from DC auto in Arizona. That was for the more expensive "125" version.

Dale_K

I had another thought about this today. Maybe one of the sensors used by the Tip to determine which "sporty" mode to use could be faulty. I think it uses lateral G sensors but I have no idea where these sensors are located or how you would check them. Maybe driving aggressively on a rough road would restore the sensors to their previous condition.

You can tell I'm just guessing. You could also drive the car in manual mode (maybe you already have) to verify the Tip is shifting normally when you control it by hand. If it acted weird or shifted poorly when you use the buttons that would point to internal Tip problems rather than a sensor problem.