# Quantum running problem



## ukquantumlover (Oct 23, 2008)

My 85 Quantum GL5 has started cutting out when approaching road junctions. If i keep the clutch just biting till the last second before stopping, it will keep running, same if i rev it a little before stopping. Has anyone got an idea where i should check to stop this.Starts agaihn soon as the key is turned. Also the upshift light has never lit up whilst iv'e had the car and i can't see a vacuum pipe fitted behind the speedo. Any idea's please. Dave. UK


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## where_2 (Jul 21, 2003)

*Re: Quantum running problem (ukquantumlover)*

vacuum leak. As for where to begin to look, I haven't a clue. 
I suspect the Quantum you have is a Bosch CIS fuel injected beast, and what you are experiencing is quite easily explained. When you take your foot off the accelerator and depress the clutch to the floor, the engine returns to idle. Without sufficient vacuum, the sensor plate in the air measuring device does not maintain adequate fuel to the engine to idle. When you restart the engine, it trips the fuel injection system into "restart" mode which boots the idle slightly.


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## ukquantumlover (Oct 23, 2008)

*Re: Quantum running problem (where_2)*

Thanks for your reply and yes, it is a CIS-E Bosch injection. Not many garages around here that seem to have a clue about this beast these days. I will go over the whole of the vacuum connections and see if there's any obvious leaks . Appreciate your thoughts on this. regards, Dave.


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## where_2 (Jul 21, 2003)

*Re: Quantum running problem (ukquantumlover)*

Dave, See if you can get ahold of a copy of "Bosch Fuel Injection & Engine Mangement" by Charles Probst. It will teach you everything you need to know to deal with CIS-E yourself, if you care to. Or, it will teach you how to diagnose it yourself so your mechanic doesn't take your hard earned $$$ and leave you scratching your head asking how that happened. 
The book runs around $20US on Amazon.com The publisher is Robert Bentley (yes, the guys who publsh the factor manuals on VW repair).


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## ukquantumlover (Oct 23, 2008)

*Re: Quantum running problem (where_2)*

Managed to get the book on Amazon like you said. It should be with me early in the week so will look forward to reading what solutions it has to offer. Thanks very much for the info, Dave.


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## where_2 (Jul 21, 2003)

*Re: Quantum running problem (ukquantumlover)*

No problem. If you've got questions about CIS I can probably lend some insight, after you've had a chance to read the book. I haven't owned a CIS car for 10+ years, but I still have a complete CIS (basic) setup in a box in my garage that came out of my '80 Scirocco_S when I dropped the KE-Jetronic equipped '85 Golf_//_GTI engine in the Scirocco. I still have an 8v KE-Jetronic brain kicking around here somewhere too... The rest of the useless CIS fuel injection information is wedged in my brain somewhere between Calculus 1 and Differential Equations... 
I find I use more of the CIS, than calculus, or Differential Equations in real life.







The CIS Textbook above only cost me $30 when I bought it new in 1993. 


_Modified by where_2 at 10:52 PM 7-15-2009_


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