Has anyone seen retro cars mag this month???

Post by **SteveP** » 03 Aug 2006 05:58 pm

Yeah definitely, but I wonder what parts that have wear are the ones that need changing...

Post by **jtbo** » 03 Aug 2006 06:05 pm

Oh yes, curse of stock efi

Cranking up fuel pressure could perhaps help? Quick test could be taking vacuum hose from fuel pressure requlator out and blocking it. Idle might be then bit too rich, but 3bar fuel pressure regulator (From 740 turbo for example) might give some help if that test shows any performance gain.

Can't remember what was that low pressure of 2,5bar regulator, 1,5 or 2 perhaps, but I think it was same with 3bar regulator but it just gives more pressure when using loud pedal. However my memory can have few glitches sometimes

Anyway I did dig some part numbers for one finnish volvo forum member and I can put them here if someone is interested?

Post by **jtbo** » 03 Aug 2006 06:10 pm

SteveP wrote:Yeah definitely, but I wonder what parts that have wear are the ones that need changing...

Injectors might need cleaning, also fuel pressure regulator has spring that might become weak, thus reducing pressure.

Fuel pump can be worn too, but I would start with injector cleaning in Bosch service or some other place where is ultra sound cleaning device, good thing in Bosch car service in here is that you get reports from each injector before cleaning and cleaning so you can see if some injector is not so good shape. Also it was not too expensive, I think it was less than one new injector for cleaning of 4 when you send them only injectors.

Also some who has send their injectors to be cleaned have reported how they clearly could feel difference how engine responded after that.

Post by **foggyjames** » 03 Aug 2006 07:34 pm

We should run a wideband lambda probe on an LE-Jet car, see what's up. Andy's car on MS pulls like a train (but with a fresh engine, of course)

cheers

James

Post by **jtbo** » 03 Aug 2006 08:44 pm

foggyjames wrote:We should run a wideband lambda probe on an LE-Jet car, see what's up. Andy's car on MS pulls like a train (but with a fresh engine, of course)

cheers

James

This is great idea, would be interesting to see what kind of results it will provide

Post by **Chris_C** » 03 Aug 2006 09:49 pm

I reckon the injectors definately... they could coke up, or what are they made of? Any chance teh opening could get bigger, pushing more fuel through per pulse?

Post by **foggyjames** » 03 Aug 2006 09:56 pm

They tend to go leaky as the internal seals fail.

You're dead right about open-loop (non lambda) systems - there's nothing to 'trim' them to take account of engine wear.

cheers

James

Post by **girlracer** » 03 Aug 2006 10:06 pm

well done Adam!