94 968 Sporadic Check Engine light and slight lack of power.

So I purchased my 968 back in January, and I've been working on it ever since. It's running ok, but I feel like it's lacking a bit of power between 2-3K RPM. It hesitates a bit. Additionally, the idle tends to fall off and it chokes off from time to time. When it's on the verge of choking off, the check engine light will come on and turn back off. I'm going to run my software again, but the first time I did there was no smoking gun and an unknown code came up. It was weird, just generic 0000 code. Has anyone had a similar problem? I've just done a full tune up with new plugs, air filter, and I replaced the spark plug seals (slight bit of oil in the plug wells, it's all dry now with no evidence of oil, so don't think there's an issue with the piston rings). What is this idle control that some mention? Fuel pump maybe??? I can't find a part in Pelican, and I really don't want to throw parts at it. Thanks!!!! and happy to be a member.

Adam L

Views: 164

Reply to This

Replies to This Discussion

Quick update, I just ran codes with my Durametric and I'm getting two codes. #34 "Hall Signal" and #21 "Hot film MAF" Is anyone familiar with those? I've also located the Idle Air Control Valve. But I don't think it's throwing a code.

I apologize if you already know what they are, I can tell you that at least.

The "Hot Film MAF" is a Mass-Air-Flow sensor


It's a black tube between the air filter box and the engine. Part #1 on page 35 of the parts PDF. If you take the air filter connecting hose off you'll see a fine grid of wire. People sell cleaning products for the wire, but I've never tried them. Here's a Rennlist discussion of the merits of the cleaners :


The "Hall Signal" is coming from a Hall Effect Sensor.


It's on Page 256 of the 968 parts manual, but isn't shown relative to any other part. Here's a Rennlist post with pictures of someone replacing it:


Chris, thanks for the reply. The old Motronic codes are kind of cryptic. I had no idea that the "Hall Effect Sensor" was the old version of a camshaft position sensor. But after some research I figured it out based on some photos. ( I think the same ones you sent). It's an updated Bosch part #. The original "hall effect" part # has been cancelled. The upgraded part's guts actually looked a little different than the original Hall sensor. But, it was all the same fittings and was located as advertised, at the back of the distributor/timing belt housing at the top of the engine. Believe it or not, I replaced the camshaft position sensor literally 2 days ago, and cleared codes. It's running SOOOOO MUCH better. It feels like 236 HP to me now. I understand that a bad sensor sends the engine into a sort of, antiquated "limp mode," for lack of a better term. I also figured the hot film MAF code was the mass air flow sensor. I haven't replaced it yet. The weird idle control issue remains, but it hasn't choked off. It's better overall. I'm going to wait and see if it spits the MAF code again. If not, it may be a idle control issue. More to follow...



Support Our Ad Partners

© 2023   Created by Ray Starbird.   Powered by

Badges  |  Report an Issue  |  Terms of Service