drift a 944

Help! I recently bought a used Autothority (APE) MAF kit including the corresponding DME and KLR chips for the turbo and injector setup that I have (all stock). The car is an 86 951 and the previous owner said the kit was removed from the same year and model.

Well despite having terrible fitment issues with the hardpipe and having to use the stock rubber J-boot, I managed to get everything hooked up and wired correctly, including the diagnostic port red wire AND the chip orientation.

(The DME and KLR chips were installed in the correct units, and the notch in the chip was installed on the same side as the notch in the chip's socket.) The decals on the Autothority chips were reversed from the decals on the Weltmeister chips that were previously in the units...?

Anyway when I try to start the car, it will crank over and over but not fire. I double checked my harness plugs, DME and KLR main plugs to make sure they are secure, and just for backup I tried cranking the car while the diagnostic port red wire was attached straight to the positive battery terminal, in case the diagnostic port was bad.

Still not a single sputter, backfire, or anything. Just cranks and cranks. NOTE: I do get a heavy fuel smell after cranking, but that could be because I am running no catalytic converter or muffler. At least I know the injectors are firing.

So my question is this, could the MAF itself be malfunctioning? It appears to be an older unit, however the seller is a well known Rennlist member here and I doubt he would sell me a faulty device. Could I have the chips installed wrong? Clarks-Garage.com states that the notch in both the chips and sockets should line up, and that is how they are installed currently. Lastly, could the fact that I am using the factory J-boot have any ill effects on this issue that the hardpipe would otherwise solve?

I've spent about 2 hours using the search function on RL and scouring many good internet sources of information, but I still can't find the answer that I'm looking for. Any help provided would be extremely appreciated!!!
Thanks!

fast951

Put your old KLR back in place, see if the car starts. If not re-install your original DME chip and test.

Make sure the MAF is getting +12Vdc.

If you are smelling fuel, you probably saturated the plugs, it might be a good idea to replace them first. Don't crank too many times, you'll be replacing plugs often.

WARNING: installing the chips incorrectly (notch on the chip not matching notch on the DME/KLR board) causes all sort of bad things. Double check your installation!

BTW. Did you discuss with the seller just to make sure he gave you the correct chips?

drift a 944

The seller described the chips and MAF as being removed from the same car, and that the chips were set for stock injectors and turbo setup, which is what I have. I can open up the DME and KLR and post the APE part numbers here, but for now all I can do is assume they are the correct ones.

To be honest, I'm a bit worried of reinstalling the previous chips. They were not OEM but rather some Weltmeister chips that I would hate to reinstall and then get fried in there for some reason. Would it be ok if I reinstalled these Weltmeister chips just to test it out?

I did double check the chip orientation, and both are correct. Everything seems to be installed and wired up correctly, so I am leaning towards the MAF being broken, however it just doesn't seem right.

I lost my multimeter, and I don't have another car to go pickup a new one or a test light... but with the red wire connected directly to the battery, I still get no start, just cranking.

John, is there a way to test the MAF itself to see if it's operable or broken?

fast951

Why would I suggest you reinstall the old KLR or DME chips if there is a risk of blowing them up (unless you install them incorrectly)? This is for testing, just to make sure the car fires up (not to drive the car).

With the MAF powered, blow through it and read the signal coming out of it. But you need a multimeter for this as well.

drift a 944

Did a little testing today, I ended up putting the Weltmeister KLR chip back in like you said, turned the key and the car fired up instantly! It idled fine so I decided to take it around the block, to see if it would drive ok through the rpm range. It seemed to pull ok through 1st and 2nd gear, but after a minute of driving the MAF plug would keep slipping off and causing the car to loose all power.

My first thought after this is to put the Autothority KLR chip back in, zip tie that damned plug so it will stay on, and then try to start the car.

If it does not start up at all again, by simply replacing the KLR chip, then does this mean the Autothority KLR chip is fried?

While driving it with the Autothority DME chip and Weltmeister KLR chip, the car didn't really feel too much stronger at all. The "butt dyno" was not impressed, but I'm sure with the correct KLR chip things would be different.

Thanks John I appreciate the help!

fast951

It sounds that you have a bad KLR chip. Have seen this many times, for some reason they tend to fail!

The KLR chip does not affect power, unless it's pulling timing because of knock. Your best solution is to find a "authentic" APE KLR chip.

BTW. Next time spend a bit more $ and get a product with a good customer support.

ramius665

Yeah!! John, your products are the best. I haven't had a chance to rebuild my 951's engine yet, but the MAF unit you sold me is looking great on a shelf, waiting to go onto the motor.

awilson40

With just a MAF install alone you really are not going to see much difference. I ended up going back to the stock set up on mine. I did tons of datalogs comparing real world acceleration times with the stock VAF and aftermarket MAF and saw no appreciable difference in acceleration or spool up.
You really wont see anything unless you upgrade the Turbo. Then you really need to go with a packaged system from a company that designs their system to work together with all the parts they supply.
I bet you would see more of an improvement with the stock intake and a good chip, Tial wastgate and a good boost controller.

drift a 944

Interesting. Well the car previously had the Weltmeister chips, as well as LR dual port wastegate, 3" downpipe and exhaust, no cat, and not the stock airbox but rather just a cone stuffed on the end of the stock AFM. So I figured the new MAF/chips setup would give me at least a good noticeable gain in HP especially after reading multiple reviews and everything. I had to pinch every penny just to cough up the $300 shipped in order to get this kit, payed another $30 bucks which left me broke for some couplers to make it fit onto my turbo (and I ended up not using them and switching back to the stock J-boot), so as much as I want a really nice MAF/chips/turbo/etc kit, it will probably take winning the lottery in order for me to afford one. A good boost controller, boost gauge and maybe a wideband o2 will be my next investment, so when I DO buy that Vitesse Stage III kit years from now I'll be ready to go!

Anyhow, I will try swapping the Autothority KLR chip back in today and see if I get any results. If the car does not fire up then I'll probably end up returning the whole setup. Thankfully the seller is a very nice and understanding RL member who is willing to refund me, and he was very helpful when I purchased the kit from him.

Anyway thanks again for the help guys. If the car manages to start using the Autothority KLR chip then I'll let you know and we'll go from there!

944obscene

Good luck with everything!

drift a 944

Thanks Alan.

Well here's my most recent analysis.

I reinstalled the Autothority KLR chip, and for some craaaaazy reason, the car started up first try. I quadruple checked the orientation when it was installed previously, so I'm not sure why it didn't start before but did now.

Anyway, took the car for a spin, zip tied the plug down so everything was good to go. Unfortunately the car did not feel much faster. It definitely made the car run smoother, and eliminated some popping during deceleration, but it would hesitate a lot right before boost and during boost.

So I think I'm just going to return it if possible.

If anyone find this thread during the search function in the future, hopefully it will prove to be helpful!

And thanks again guys for the help.

minho78

Hi, Well I bought an Autothority kit on ebay sometime ago. I installed everything and somehow the car would run like crap at idle. I tried to adjust the potentiometer at the MAF without any luck. Finally I decided to call Autothority to check on the chips and MAF and they told me that the chips werent real autothority chips. I was shocked and ended up buying most of the parts from them. I spoke with Minh Nguyen and he gave me a break in a couple of parts. I don't think that you'll gain the claimed 88HP, but it sounds nice.

minho78

Just to add that the symptoms that you have on your car look a lot like the ones that I had.

alxdgr8

Do you have a wideband? 3bar fpr?

drift a 944

Interesting, I guess I could have done the same about the chips to see if they were real.
Now that you have worked all the bugs out, how does the car run? Any HP gain at all? Mine felt like +/- 1HP


Nope on both. The chips and everything were supposed to be set to run with a stock fuel system, so that's why I jumped on the deal.

I will get an AEM wideband and 3bar FPR soon though. I found a great deal on a brand new in the box Lindsey Racing ST2 maf kit with #55 injectors and K&N filter all brand new, that I think I might get and try to set up right.