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New owner here, just picked up the car a couple weeks ago as a project and I could not take this on without some of the great resources online. I've been working out some electrical gremlins and ended up doing an LED lighting conversion except for headlight and fogs. It needs a fair amount of work just to pass inspection, it seems as though virtually everything is original meaning dry rotted brake hoses, loose tie rods, ball joints, wheel bearings etc. I will be replacing all fuel hoses, water pump, belts, weeping cam seals, and some fun stuff like electric fan conversion, air pump delete, and full exhaust.
The engine runs great but on a cold start the idle revs up/down continuously between say 800 - 1800RPM until it warms up and then it has a steady idle with a stumble here and there. All vacuum lines have been replaced. Could this be caused by a bad "vacuum limiter" valve?
Another odd thing, this is a manual and I've replaced the shifter bushings and rear shift coupler which had no bushings left and the stick leans to the right. It takes the normal amount of tension to bring it to the middle and then double that to go full left to shift into rev or 1st. Has anyone experienced this? Not a huge deal but weird. Thanks in advance and for the awesome how-to's on here.
Last edited by Majestic Moose; 07-07-2017 at 10:55 PM.
the shift coupler in the rear needs to be rotated at the shift rod it adjusts both in and out as well ....you are probably hitting the console when you go for 1st-reverse...
the shift coupler in the rear needs to be rotated at the shift rod it adjusts both in and out as well ....you are probably hitting the console when you go for 1st-reverse...
Well even at the transaxle input shaft it stays rotated. You know how you let go of the shifter in neutral and spring pressure should move it between 2/3rd? It is as if my springs that should oppose each other are on the same side. Hard to explain.
Oh another annoyance, the blasted early style seat switches! Lots of info on the later four way style but I haven't found anything about these. My driver seat only moves back. I've opened, cleaned, and fiddled with the little leaf springs inside but cannot get them working 100%. I know the motors all work by using a good switch from the passenger seat. At over $70 bucks a piece someone must have figured out how to fix these.
Well even at the transaxle input shaft it stays rotated. You know how you let go of the shifter in neutral and spring pressure should move it between 2/3rd? It is as if my springs that should oppose each other are on the same side. Hard to explain.
Oh another annoyance, the blasted early style seat switches! Lots of info on the later four way style but I haven't found anything about these. My driver seat only moves back. I've opened, cleaned, and fiddled with the little leaf springs inside but cannot get them working 100%. I know the motors all work by using a good switch from the passenger seat. At over $70 bucks a piece someone must have figured out how to fix these.
It's 100% correct and normal for the shifter to center in the 4-5 gate.
Nice looking car. I recommend getting the fan shroud. Your venturi intake tubes right now suck hot air straight from the engine bay. The upper shroud part has vents for the tubes to attach to, and pull from above and in front of the radiator where the air is cooler. 928 International sells them used.
As to your cold start idle issues, not sure what is going on there. I do not believe the L-jet uses a cold start injector, but I do not know for sure. My 78 is a mechanical CIS injection system (K-jet) that uses a cold start injector, and what you describe is what happens if that injector goes bad. You have a MAF I believe, and so your issue could be related to that. Hopefully somebody with more knowledge of the 83/84 will chime in.
My old merc used to have the cold hunting issue and this was caused by the idle being set too high, the ECU sees the idle position on the throttle but too many revs and thinks its in overrun and cuts the fuel until the idle drops. This only happened at idle and cold when more air is being added by the bypass valve as well. Could be a big vacuum leak or badly adjusted idle bypass screw.
So I am in teardown mode. I wasn't planning on going as far as I am but the further I get I think "well, while I'm in there..." The steering rack developed a leak while the tie rods were hanging overnight, so I have a rebuilt rack coming, power steering pump rebuild kit, and hoses.
It looks impossible to replace the exhaust manifolds without removing the center cross member so now I will be changing the engine mounts and dropping the oil pan since it is leaking. Oh and as it turns out I have the dreaded aluminium lower ball joint mounts. So were these officially recalled but some people never went to get them replaced?
Now I've got a couple questions, I found this plug or cap on the ground and if it belongs on the car maybe someone will recognize it.
While taking out the clutch slave I found this kind of toothed washer loose in the viewport. How critical is this part?
Last edited by Majestic Moose; 07-07-2017 at 11:08 PM.
A- Ha ! ! You have found the "While-You-Are-In-There" rabbit hole ! !
There are many different entrances to the 928 Rabbit Hole. I found mine by way of a cam tower leak.
Have fun, take your time, and ENJOY the trip. If you start getting frustrated, just take a deep breath and think about how AWESOME your car will be when you get finished
Hmm I don't see it on the PET. Looks like I'll have to drop the clutch housing to get it out though, the clutch release lever is in the way to come out the front clutch slave port.
EDIT: I have found it looking at pictures of new clutch slave cylinders, I wonder how it came out.
Yeah it is a rabbit hole, I've now spent as much on parts as I paid for the vehicle but I see it as a good cause. I can tell there is a lot of deferred maintenance when I see made in West Germany stamped on parts but I am pleasantly surprised how easy it is to work on a vehicle of this age. I seem to be constantly battling seized bolts on vehicles that are only a few years old. So far so good.
Last edited by Majestic Moose; 05-25-2016 at 06:22 PM.
So Ducman82 you were right on. My clutch slave cylinder must have been replaced because it had its own 'toothed washer' in place. I dropped the clutch inspection cover which was remarkably easy and the stray part fell right out.
Next I removed the old upper A arm ball joints which I thought would be a major battle, again I found this satisfyingly easy. The old epoxy chipped right out. Since the A-arms are coming out to replace the bushings I will wait to install the new ball joints so I can clean up the A arms.
Then I was able to completely remove the air pump system
I took off the passenger side rear cam cover and found the bolts very loose but I have a question, there were only three bolts but there are four holes in the cover. Also, made in Canada? Has this been replaced in the past with the wrong part? I haven't taken the driver side cover off yet to compare.
I've also taken out the passenger fuel rail and injectors and if you look closely at the one on the right it is a different style with a pin sticking out. Is this non OEM and should I source a correct injector?
That's all for today.
Last edited by Majestic Moose; 07-07-2017 at 11:16 PM.
05-14-2016, 03:58 PM
1983 928S
