What's the situation? You boost'n?

 

Not yet, and haven't had time to hook up the fitting to pressurize the turbo circuit yet. Did drive her around town today with nothing clamped and we're still not making boost. Going to get back under the hood tomorrow, do the pressurization check and touch a hot wire briefly to the CV as suggested by someone here earlier. Barring a pretty substantial vacuum leak, I'm leaning towards the CV as the culprit now.

Thanks much for the continued interest and support! Will post up results as soon as I do some more troubleshooting.

 

Two tests completed today.

Tested CV via hot wire from the battery. Verified the wire was hot and touched to both terminals on the CV. No clicking of any sort at either terminal. Based upon this test and readings on Clark's Garage, this would lead me to believe I may have found the culprit. Concurrence?

Clamped my pressurization adapter into the turbo end coupler on the IC and pressurized to 10-12 psi. Three discernable leaks, and all seemed to be very small. One at the throttle body, seeming to come from the shaft area. Easy fix with a throttle body rebuild. Another coming from the CV, apparently from the terminal area. Normal? Lastly, a hissing coming from under/near the CV. There's a hose, similar in size to the CV to WG hose, that runs past the CV into the rats nest under the intake. When I move this hose a bit, the hissing changes proportionately.

So, can anyone offer agreement that it sounds like a bad CV may be the root of my boostlessness? And as a follow up, would you replace the CV with another stock unit, or go with an MBC?

As usual, thanks much! Your inputs have proven invaluable.

 

Sounds like the CV is your issue. These things like to crack/break with age, and if the original rubber is still on there connected to the metal "squid" under the intake, then all that will need replaced (5/16" fuel hose works great). I took mine out a week or two back, one of the lines had been replaced, one hadn't, the one that hadn't cracked in my hand. The CV had been repaired several times, the 3 nipples were JB welded back on, and underneath there were more cracks that had been fixed with JB weld. Even with all that JB weld the thing still leaked, from around the connnector like you said, and from another crack that had formed since it had been originally repaired.

I'd find a good used CV if you don't plan on doing any mods in the near future. Also check your J-boot for cracking and dry rot. If it leaks between the turbo and AFM it can lead to some weird drivability problems. Pick up some new fuel injector O-rings, intake manifold gaskets and a TB rebuild kit and just do all the work in a day. You'll end up saving time in the end.

 

Sorry, that CV test isn't going to show anything. The cycling valve is turned on by grounding pin 2 of the KLR which is the Blue/Red wire going the the valve. The ignition has to be on to apply power to the other side of the valve which is a Red/Green wire. Touch the wrong pin, and you will get lots of sparks and hot wires since that is a hot lead right from the DME relay. Best to put a fuse inline with the test grounding wire.

 

Ahhhh, silly me...thinking I could get some conclusive results with a simple test! Ok, not back to square one, but not the progress I was looking for either!

Out of town for the next couple days, but will follow up with this new version of the CV test later in the week.

In the meantime, I do know my CV is leaking. Anyone got a good used one they're willing to part with?

Thanks much!

 

Alrighty then, update time.

Swapped out my CV with a known good used unit today, and lo and behold, we built boost! So I know we've solved a big part of this equation. However (isn't there always a 'however' with these dang cars?)...

When building significant boost for the first time, she lurched, popped once (origin unkown) and took off again. Lurched a few more times over the course of the ride and actually completely died twice. Starts right back up each time. DME relay swapped out. No fix.

Next up on the list of things to do is a general tune up. During the course of an oil change, after taking off the distributor cap for access to the filter I couldn't help but notice how terrible the cap and rotor looked. Haven't pulled the plugs yet to have a look, but there's no reason to think they'll look good. I'm detecting years of neglect by PO. So anyway, before I start going to far down the road of "what the heck can THIS problem be?", I'll be taking care of the basics.

In summary: Progress. Built about 1.75 bar of boost before the lurching and generally poor running situation arose. So tune up and probably vacuum hose re-do on the near horizon.

Thanks to all for your help and suggestions as I continue to work her issues!

 

So how did you like the feeling of the boost for the first time? Intoxicating, right?

 

I said you coulda' used mine...

Glad it's up and roaring again!

 

And I appreciated the offer, just went with something a little closer to home.

As far as being up and roaring, well let's just call it a step in the right direction for now. Still clearly a few other issues to work out, but it sure was nice to see the boost gauge climb beyond 1 and feel a nice little kick in the pants.

 

Yeah, I'd say a general tune up is in order. give it new plugs, wires, dizzy cap and rotor, maybe a coil, and make sure that the iggy system is working as it should. fluids, filters, etc. That may help with the stuttering. every time I've had stuttering, it's either from a rich condition, or a spark issue.

 

+1 on Pfile's advice. The budget will take a little hit, but its stuff that needs to be right before the fun can start. I'm fortunate that the $2-300 weekend maintenance updates once a month don't kill me, but I'm guessing there are LOTS of 951s in the hands of people that only fix them when they're broken/won't run. I hate that my 951 is way down on the "vehicle" spending list. 5 cars/truck, 4 motorcycles, 1 airplane gobble up $ too quickly. Having said that, I put 150 rural miles on it yesterday, and I think I'm going to move it up on the priority list. It was that much fun.

Sorry to editorialize, but the moral to the story: Your car is close, and I believe you'll love it once all your boost is present. At least enough that the spending feels justified!