# CIS-E motronic fuel distributor not holding pressure



## Keithcar (Dec 30, 2010)

Guys, Ive been having trouble getting my car started lately. It's been getting progressively worse, now it won't start up without me raising the metering plate and running the fuel pump, to "prime" the engine. 

The weird thing is, on it's first startup of the day, it will fire right up just fine. This is on a typical 70 degF day. If I kill the engine, it won't fire back up. The starter motor will just spin the engine over.


I took the distributor off and I notice the plunger in the middle will dribble fuel out whenever it is moved. The fuel just drips in the airbox and eventually evaporates I guess. Is that leak causing my injectors to loose pressure or something? hence the engine not wanting to fire up?

I know its not supposed to do that, but i can't find a sealing-ring kit anywhere for that part of the distributor, and it seems my only choices are other used distributors on ebay, or rebuilt ones that are 300+ dollars.. 

what do you guys think? any help would be great. I need to be driving this car again!!!:snowcool:


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## Keithcar (Dec 30, 2010)

I forgot to add, that when i rev up the engine, the air intake boot covering the metering plate collapses down, as if the airflow is being restricted somehow. I didn't notice it doing that before.

the airfilter is a freshly cleaned K&N


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## ziddey (Apr 16, 2006)

There will be some degree of collapse before the airplate is able to lift, since it is under pressure.

Don't know what to say about the leak. I've found that cis distributors go for around $40 at picknpull though. Pretty quick swap to test.


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## WaterWheels (Aug 14, 2005)

Been away from CIS systems for a few years now but if I recall the adjustment nut under the fuel distributor plunger is also a seal of sorts (CIS-e and CIS Motronic). That is the basic reason for the change made from the older CIS systems, to have a "rest" position that seals off the plunger. Because of this change, the two newer CIS based systems require a few added checks and adjustment from the older systems. The plunger stop nut has an adjustment and the air sensor plate has two settings. Have you checked the air sensor plate adjustments? If it is sitting too low it could cause problems like you are having. Too high will also cause problems but you should not see any boot collapse as too much air is then entering. 

That collapse really needs to be explained better. Some systems, can't remember just which models, had weak boots and VW installed a support up inside the boot to keep it from flexing. They also did it for back-firing through the intake so it was more like a screen. Newer systems had much stronger rubber boots and the support was discontinued as they only flexed slightly under extreme pressure differences. If yours is collapseing real bad then something is blocking in-comming air. The sensor plate being too low could do this a little but also a very dirty filter, birds nest or clogged front air intake.


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## Keithcar (Dec 30, 2010)

Waterwheels, you are pretty much spot-on. This is actually the second fuel distributor I've had on the car. I spent some time verifying that the retaining nut for the plunger was adjusted correctly, and that the meter plate's roller mechanism was at the correct height. It was a huge PITA, but I got the car to run well after a lot of tinkering and checking the DPR current etc. The meter plate's height in the cone seemed to be correct according to the bentley. 

It was a gradual thing that started taking place, thats the only reason why i thought it might be a seal starting to get leaky.

I ended up finding another motronic fuel distributor assembly on ebay (from a 9a passat) with all of the crap already installed on it, hopefully it will get me on the road again without having to fuss with any settings.


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## Keithcar (Dec 30, 2010)

I actually replaced the original intake boot with a meyle one, it seems much softer than the original VW one. Probably explains some of the deflection going on. There is no obstructions in the intake that i can see.


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## Keithcar (Dec 30, 2010)

I ended up swapping the entire upper intake assembly with a 9a passat unit. 

The car does start now, and seems to run pretty dern good. I havent fooled with any settings whatsoever. The plug on the meter plate housing covering the CO% screw is still intact! 

Anyways I still have to run the starter for a few more seconds than i'd like to get the car started.

Somebody mentioned there is a pressure valve under the car, on the fuel pump housing. Was he referring to the little check valve/banjo fitting that actually screws into the main fuel pump???

If that sucker gets leaky, the main pump and lines after it loose pressure i assume.


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## pcris003 (Jul 14, 2011)

Hi, I am having a very similar issue you were having. My injectors wont spray anything with the plate resting and if i lift it up slightly, it will spray fuel. I have pressure from from the pump at the distributor but nothing to the injectors. Would this be a bad distributor or something electrical causing it like DPR or something?


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## nthndetty (May 10, 2006)

Bump. Same problems


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## 53PL-50AAA-VW611BAN (Feb 10, 2015)

Keithcar said:


> I took the distributor off and I notice the plunger in the middle will dribble fuel out whenever it is moved. The fuel just drips in the airbox and eventually evaporates I guess. Is that leak causing my injectors to loose pressure or something? hence the engine not wanting to fire up?
> 
> I know its not supposed to do that, but i can't find a sealing-ring kit anywhere for that part of the distributor, and it seems my only choices are other used distributors on ebay, or rebuilt ones that are 300+ dollars..
> 
> :



I'm glad you got it working with a replacement distributer. 

The kits these guys sell have this seal:

http://www.ebay.com/sch/cis-jetroni...1&_from=&_ipg=50&_trksid=p2059210.m2749.l2654

Geez, I must sound like I work for them. I'm just a satisfied customer who has bought a few kits from them.

Sincerely,

Eric


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## jimbbski (Jun 3, 2007)

pcris003 said:


> Hi, I am having a very similar issue you were having. My injectors wont spray anything with the plate resting and if i lift it up slightly, it will spray fuel. I have pressure from from the pump at the distributor but nothing to the injectors. Would this be a bad distributor or something electrical causing it like DPR or something?


Without the plate moving from it's rest position no fuel will flow to the injectors. At idle the air flow will lift the plate a bit so I'm not sure what your problem is?


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