Rufus Sanders

I hate to say it but you may have a slipped T-belt, off by 1 tooth or mayabe two, and maybe on just one side. Just saying... - Ruf

Pfc. Parts

How does the differential diagnosis work on that? I understand the air, fire, fuel diagnosis, but this is much more subtle. Why would we consider looking here? Are there any stand out symptoms to indicate cam timing?

Thanks,

PS. I've taken the timing belt off on one of these before and I'm a little confused about the "maybe on just one side" qualification; How can that happen? Wouldn't you expect the belt to even out to at least 1 tooth after a few revolutions? I understood that to be the point of re-tensioning the belt after 500 miles?

Pfc. Parts

Never mind Ruf; I got it.

The cams can be off by any number of teeth. You meant the *cams* might be off on either side? Sorry for the misunderstanding. I'm sort of visual and while I was working on the problem I was looking mostly at the cam teeth and the way they related to the TDC marks on the cam and vibration damper. I never thought of skipping teeth on the T-Belt; always in terms of mis-timing the cams

928wolf

Dumb question alert: Do you have a pin out diagram for the LH control unit plug? The one in the service manual has 35 pin locations, I think it is for later models or something because it doesn't match mine (25 pin locations). I am trying to do the same measurement (Pin 7 and Pin 9) on my '85 Euro and I am not getting voltages that make any sense (most none at all). Where is the best place to get a good ground connection near by? I am grabbing anything metal that should be grounded near there but no luck. I am supposed to be measuring the plug, not the actual controller, right?

I'm sure I'm doing something really wrong, but I can't figure out what.

Thanks,

PorKen

'84-'86 16V and 32V EZ-F and LH2.2 plug pinouts - https://rennlist.com/forums/928-foru...2-pinouts.html

85euro928

Wolf,
What problem are you chasing?

928wolf

I have all the symptoms of an MAF that needs to be rebuilt - poor performance/lack of power in the power band, jerky acceleration, etc. I'm just trying to do all the checks before I spend the money. Measuring these voltages is the last of the 5 measurements John Speakes recommends on his website. My MAF pot is over 1000 ohms (1053), 4.2 ohms at the sensor resistor, I measured battery voltage at the MAF plug. When I disconnected the MAF performance certainly got worse, but not dramatically worse.

I'm trying to make sure there isn't some other problem that a rebuilt MAF won't fix.

Thanks,

928wolf

Awesome! Thank you

(I obviously don't know how to use the search function on this website, I spent a half hour looking for this very thread and got nothing)

928wolf

85Euro928,

I hate to keep high-jacking your thread but, I am getting my MAF rebuilt as we speak. When it gets here I will have to set the A/F ratio. You appear to have a lot of experience with this on my identical car, so a few questions: what equipment do I need, where do I pick up the exhaust, what A/F am I looking for at idle and any other rpm's I need to check? I already figured out from another thread that the air pump needs to be disconnected or it will lean out your measurements.

The service manuals have a procedure to check CO in the exhaust. A CO tester looks quite pricey, so I am planning on getting a wideband O2 sensor.

Any Rennlist write-ups on this for Euro 16V engines?

Thanks,

Mrmerlin

https://rennlist.com/forums/928-foru...?highlight=maf

https://rennlist.com/forums/928-foru...?highlight=maf

85euro928

Wolf,
For equipment you need some way to measure the RPM's besides the tach, and some way some way to measure the AFR. To measure the AFR I use an Innovate LC-2 but you could use a VOM, like Merlin describes in the links above, tied to a wideband O2 sensor. If your car is like mine was you have a cat swedged on to the existing exhaust with an O2 bung (probably with an inactive O2 sensor). If so buy a new WB O2 sensor and use it with a VOM or buy an Innovate or other system to read the AFR. If you don't have the bung you're going to need to find some other way to measure the AFR (like a friend with a shop that does Inspections?).
Once you get all that set up run the car to operating temp (but not too hot) and set the RPM's to 750 or so.
Then tune your MAF so you achieve 1 to 1.5% CO which equates to about 14.0 AFR at idle. From what I've read that's what the Euros like, for reference, when mine was running, it seemed to like it at 13.9 but that could just be my car.
As far as write ups are concerned specific info about the Euros is not as available as some of the other models but a lot of info here on RL regarding other models applies to your car as well, you just have to weed through all the information and then decide what applies to you.
Lastly, if you have the opportunity to check the AFR above idle you should do so as the rumor is that these cars tend to run lean.
One more thing, look in to John Speakes chips for the Euro. I installed them a few months ago and although I can't speak as to whether they added the advertised HP/torque except for the assometer, I can say that they did make the car run much, much smoother. You'll need to check your LH and EZF first to confirm that your existing chips are installed in sockets and not soldered in.
Good Luck!

Pfc. Parts

You may want to look at PorKen's Blinkr':

https://rennlist.com/forums/928-foru...-85-86-us.html

I used it to adjust my MAF after an intake refresh. He mentions the tool has a very narrow response range and I found that to be true; I couldn't use it at all until I'd corrected my vacuum problems, but once the engine is basically sound it works very well.

Regards,

Louie928

Before you get too involved in getting additional equipment, try adjusting the MAF idle CO pot by ear. Set it for best idle just like you would do when adjusting the idle mixture screws on a carb. It isn't difficult.

85euro928

Scott,
As far as I know the Blinkr won't work on a Euro.

Pfc. Parts

Sorry to hear that. No diagnostic port?