Turbo Conversion Initial Thoughts
 

The good is the car is running well at idle.
The bad, if I try to push down on the pedal, it stumbles, like a fuel related issue.
As soon as I take my foot off, idles fine.
I have not yet had time to get a wideband on it to see where the ratios are and tune it, but hope to this weekend.

Any idea what it could be? I know the description is a little vauge. It is an SC with a 930 CIS on it.
SC fuel pump, SC Fuel Accum, and filter.

Should a Euro CIS have a frequency valve?

The euro CIS fuel head has no fitting to install a lambda frequency valve and one wouldn't work right on it if you drilled and tapped a fitting in it anyway.

Thanks for confirming. Any other thoughts? or is it too soon to tell with out finding out wha tthe AFRs are?

If it is way to lean accelerating above idle then a motor will usually stall or die out in a smooth all at once way with no bucking or misfiring and with no smelly hydrocarbon black exhaust smoke when you open the throttle, and if it's way too rich they usually misfire and chug and buck while trying to accelerate with alot of overly rich fuel smelling black or dark grey smoke coming out the exhaust.

Used spark plugs will be black, sooty, and possibly wet with fuel if it's way too rich and they will be clean and very light colored and the insulator will be almost white if it's too lean.

Thanks for the info, I have really not had the car running past idle more than ~2 min and I shut it down b/c I was concerned I may be way to far one way or the other.
I did not notice any black or greay smoke, just some on start up and then it quickly clears.

I also have not accelerated it long enough to get it to die, so it may be too early to tell yet.
There also seemed like little throttle response when I would hit the accelerator quickly to try to rev it, or that it was not smooth.

ok couple question
1st you are positive all the plug wires got back to where they need to be?

2nd pull all the injectors and verify they are all working (glass jar etc)

3rd make sure the plunger is not stuck

4th make sure there is no leaks in the cis as to not be able to pull the plunger with vacum

5th WHat it does not run like mine;)

call me if I can help any further

I was able to get my hands on an LM 1 for the night and at idle the car is @ 12.5 and as soon as I start to accelerate, buy 1100 RPS I am already at 14.5

How is this corrected?

Well I am not a master mechanic... but seriously your car is bad a** and goes like hell!!

Throttle response seemed fine. I took it up to ~5500 (still in my garage) and let off. A couple of loud pops, but I guess was running fine.

Cant wait to actually drive it to see where we are at.

You likely have a fuel delivery issue. Mine does the same sort of things. I just ran mine tonight for the first time in two months....stumbles, no power on boost at revs. I can make some of it go away with the boost retard control turned up to 3 deg per pound. I turned down my warm control pressure to 34 psi and same thing. It may be ignition, but it;s usually fuel. AFR's were going up a bit, so it may have been running out of fuel.

I had it running pretty good in May. It was colder weather. The SC fueling system is very finicky with ambient temps and a stock fuel head. Shaking out a homebuilt turbo system requires a lot of head banging, I have found out.

You are obviously running lean, look for leaks in your vacuum system.
biggles

Where are the typical porblem areas for leaks?

Check the connection at the throttle body, or even actual vacuum lines, may have gotten pinched. Have you checked your FP?

I hope to get a chance to look at it today. Have to get a can of carb cleaner. FP? fuel pump or puel pressure?
Thanks.

I pulled my car out of the garage, just a few minutes ago, first time since last October!
When I started it, I had similar symptoms, didn't fire right away, sluggish response, but slowly got better.

While running, too a peek in the back to see if I see anything obvious and noticed this.

http://forums.pelicanparts.com/uploa...1312150000.jpg

The vac line from the WUR to the air box is too long and is crimped? COuld this be the source of the issues?

I am going to pull the IC, shorten the hose and see if that helps change the AFRs or the hesitation when first starting.

Fixed the hose but no significant change.
Sprayed carb cleaner around the intake, IC connections and did not hear any change in idle.

Took the car "around the block" but did not even get it out of first or past 1800 as the AFRs were in the 17s so I was too hesitant to go any further or harder.

FP - Fuel pressure. Are you using an adjustable FPR? If so, I would increase the pressure and see whether it changes your readings.

It's furel related vacuum leak will cause it to rich!

What is the best way to check FP? What should the FP be at? If it is low, how is this adjusted. Thanks all.

I have a cis tester you are welcome to use.

I'm working my way through this myself as of Saturday. You'll need to check hot and cold control pressure, overall fuel pressure, then fuel delivery rate. First you'll need to get mb911's test setup. And as long as he's delivering it, have him help you run the tests.. as he knows what to check :-)

Sorry Cant help:) just can borrow the tools to do the job;)

Yes I will need it, thanks.

Got the set up, unfortunately Ben's not able to assist. Is there a good post I can use for reference? I will continue to search...

OK Here is the update.

WUR unplugged, car sat overnight.

1. Key (Ign.) on valve closed
2. Key off valve closed
3. Key off valve open
4. Key on valve open
5. Key off, valve open, sitting ~10 min

http://forums.pelicanparts.com/uploa...1312643731.jpg

http://forums.pelicanparts.com/uploa...1312643748.jpg

http://forums.pelicanparts.com/uploa...1312643848.jpg

http://forums.pelicanparts.com/uploa...1312643866.jpg


http://forums.pelicanparts.com/uploa...1312643891.jpg

With the car running and taking it up to ~2K the needle fluctuates a little but not much.

Had some hunting when the AFRs were ~10.5, but dialed it back to ~12.0-12.5 at idle. Not sure where to check next, as soon as i hit the accelerator the car leans out.

If I understand correctly, your fourth picture is with the fuel pump on and the valve open, with the WUR cold. That pressure seems to be the same as the system pressure. Seems way too high, which would yield a very lean mixture.

Did I do the test right? I Unscrewed the line to the war and put gauge in line between the fd and wur. The valve for this tester is not below the gauge off one of the hoses. If the fuel flows from the fd to the wur should the valve be before or after the gauge? I connected it so that the valve was after the gauge.

I have just seen your other threads about the wur. Yu can search my name. In my " no start thread" I test the wur amongst other things. I make all the mistakes. I guess you can make so read it carefully and the help I got will answer your questions, I think.

It would be great if you could get a factory manual. It has the procedures laid out along with pctures.

Good luck.

Thanks jesper is there a thread on the disassembly and cleaning of the WUR?

I don't know if there is one here on PP, but I would think so.. Maybe on the tech forum

I found an article about wur rebuild somewhere else. It was for a merc, but it's basically the same. Search on google.

If it find it again I'll let you know.

Here is a post on testing your WUR jcc.

http://forums.pelicanparts.com/5975236-post2.html

Ok here is the update. Because I have seemed to isolate the pressure at the WUR, I removed it and put the gauge in line with the fd and the pressure was relieved.

Next I disassembled the WUR and inspected it. There was some corrosion so I cleaned it the best I could and out it back together. Put it back on the car and the same issue, high control pressure. The only part I didn't inspect was the diaphragm under the disk, so I pulled it back of and completely disassembled it. The little plunger that pushes on the metal diaphragm seemed stuck so I removed the four little screws and pulled the disk and diaphragm off. I popped out the little plunger and ran a fine sand paper around it and the hole it sits in. It now moves up and down freely.

I then put the top half of the WUR back on the car and checked the pressure...0.5 bar! So far so good. I then took a center punch and gently pushed on the plunger and the pressure increased. So I know the top half of the WUR seems to work! On to the heating element and lower half.

SUCCESS!!! Upon reassembly of the WUR, I tested the cold control pressure and the gauge now reads 3 bar.

Next I will test the warm control pressure. Start up and driveabily should be drastically better now that control pressure is not as high anymore.

That sounds like progress. Awesome.
Good job.

Started the car and let it run ~5min and the pressure increased to 3.65 bar.
AFRs were 12.0-12.2 at idle.
Blips of the throttle still showed the car to go lean.

Now What??

I noticed this AM that the gauge reads 0 after sitting overnight, shouldn't it be ~1 bar still?

Just because the WUR is working doesn't mean you're getting fuel. The next step is to check your fuel delivery rate. Not sure of the spec but you'll need to take an injector off and measure the amount of fuel per given time.

Good point as I do not seem to find a vacuum leak anywhere.

Would I have to pull each one? I suppose it wouldnt hurt as I could also check the pattern.

Or is this done by checking at the return line?