I've been getting an increasing number of "restricted performance" warnings on my'99 xk8. The accelerator stalls and sputters under this
warning. It usually passes after a couple of minutes.

This may be a stupid question, but if I hook up a code reader, does the
car have to be running? Will codes pop up even if the "performance" warning is not on screen at the time of analysis?

Is this something the guys at Autozone can hook up and test for me?

Thanks for the help, guys.

 

Not an expert ,but they say correct procedure tells ignition II no engine running . I have tried both ways with and w/o engine running each time I could easily erase the codes .

 

Ignition must be on, engine. does not have to be running, but can be.

The codes are stored, so you do not need a current warning or fault indication to read them.

Most Autozones will do it for free, but a basic code reader is not expensive these days.

 

As a matter of habit I don't clear codes with the engine running. I did that once with my Corvette and it didn't like it.

I've become a big fan of the Torque application for Andriod phones. It has the ability to read manufacturer specific codes in addition to the generic emissions codes you'll get read at Autozone, et. al. (The Reverand, here, posted his Torque set up recently and it was impressive and inexpensive - the post has links to the software and Blutoooth adapter you will need.) If you have a smart phone it's the way to go - or, in my case, a good excuse to get one...

 

I loooovvvve Torque. It gives so much info for so little money. I'm amazed by the program. And the developer seems to send out updates about once per week for no charge.

I've used to to read and clear codes with the engine running (driving down the road, actually) with no problems whatsoever.

 

Clearing codes resets 'learned' fuel trims, timing maps, etc. That's why you'll see a P1000 after clearing - the specific driving parameters needed to complete the learn cycle have yet to be completed.

 

Thanks for all of the help, guys. I'm running all over the previous posts trying to find
Rev Sam's setup for the Torque program. Anyone have a link handy? Sounds like a
sweet way to go. Ed.

 

Torque — OBD2 Performance and Diagnostics for your Vehicle

 

Here's the Bluetooth device you'll need

$52.99 - ELM327 Bluetooth OBD-II Wireless Transceiver Dongle - OBD/OBD2 Car Diag. Tools

 

I looked over the Torque videos on Youtube - the ones I saw were very lame and totally missed it's real value features. Everyone does the same thing - turn it on, look at the default Rev counter and show that it tracks the one on their dashboard. One guy went totally wild and drove around the block silently letting us watch his boost gauge move slightly. Plus, all these guys have brand new cars with no real issues, so they don't even know how to access the fault reader, let alone learn anything from it... Hopeless.

We should make a real useful video - sort of a Level 2 Diagnostics from the XK8 community. Maybe it could show how to identify a fault code, set up a custom data screen and capture fuel trims and data log them to diagnose a leaking intake plenum, fix it, clear the code and relog the trims to show the change.

Their website has a forum that is pretty interesting.

I have received 2 updates over the last 2 weeks.

 

Spurlee, I know you were talking about a different car...but I thought it would be worth mentioning that the XKR's MAP sensor which is read by OBDII will not read positive manifold pressure above around 5 PSI or so. Therefore Torque cannot be used on an XKR to monitor boost accurately...though it can give indication that there is 'some' boost.

 

I think Torque is going to show you whatever info your OBDII puts out. The one I bought gives lots of info, even abs codes, but others might not do that. I honestly don't know.

 

Here's the exact one I bought. http://www.dealextreme.com/p/elm327-...r-dongle-16921 It's more compact than some of the others I've seen. I just left it permanently attached to the OBDII port, but I still kept bumping it with my knee. until I broke it. Then I realized that the top half of it is just hollow. I didn't glue it back together, I just wrapped it with black electrical tape. Now it's half the height, it blends in, and I never bump it with my knee. It's always on when the car is on and I always have my phone with me, so I can easily turn on Torque and read the cool info about the car. It's mostly just a toy for me, but it comes in handy for reading codes and stuff.

 

Now I get it, the type of data that's exported is determined by whatever OBDII dongle you buy - they each reflect different sets of reading software.

Presenting whatever data is exported is handled by Torque but it doesn't determine what type of data is getting pulled.

Am I right?

 

That's what I assume. The dongle can't send the data to Torque if it can't interpret the data from the car. If the AutoEnginuity could communicate with torque I'm sure Torque would show transmission temps and everything. In the Torque setup tranny temp is one of the selections, it just doesn't work with my dongle.

 

I see, it's more than a signal braodcaster.

Then the trick is to find the dongle that can interpret the greatest number of signals (codes). You found a good one because it can interpret Chassis/ABS codes.

Maybe there's one out there that can interpret even more.

I imagine the technical hurdles are very high but just to ask, could one be made?

I know nothing about electronics, but if we can make the top go up and down via the key fob...

 

Boy, ask a silly question and get a college degree in code reading technology!

You guys are awesome. Thanks again for all of the help, Ed.