I @&*#^$ give up. [very long]

Ok, now I'm stumped. Put the resurfaced (including upper) intake back on. Torqued in 2 phases as per Haynes. NOW I get 15" vacuum, and it still runs rough. Got 17" before.

Injectors are freshly cleaned and flowmatched with new seals.
Also put new ECT and ACT; they failed the ohm tests posted here. The new ones from napa are plastic, so I used teflon tape, not the goo, on the threads.
New Fuel pressure regulator, and all new gaskets.

At least I got 17" before all this!
OH YEAH!
One of the metal coolant tubes on the IC side now leaks. WTF!!??? Where the hell am I going to get those?? NOW I can't even DRIVE it.
Also, I hold the rpms around 2000 to 2500, the vac needle now vibrates 1" or so. But NOT ALL THE TIME.
It'll clean up for a moment or 2, then miss a bunch and the needle vibrates. The needle was solid before! Also at idle I can feel moments of clarity, it's definatly not doing it all the time; but it is 90% of the time rough.
The ony thing that I can think of is my intake is sealing better, causing a different <real?> reading reflecting my BRAND NEW hla's..one or 2 of which are probably bad??
Or I even thought maybe the gasket on the lower to head doesn't REALLY seal until it gets hot for a long time?
Suggestions, PLEASE!



[This message has been edited by Matt S (edited 07-27-2003).]

Replace the metal coolant lines with copper tubing / brass fittings from the hardware store, and short pieces of silicone hose. I fabbed up custom copper lines for my water cooled T3 conversion, and they are working fine after 3 years.

Vac / rough running: Are you sure the valve and ignition timing are correct? The lower intake to head is difficult to get on, as you must know. I bet you have a vac leak at the lower to head, or another vac leak somewhere. What cam are you running? With the stock cam, or RR cam, you should be getting lower than 17" at idle... more like 19" to 21".

------------------
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 20 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 02 Taurus Vulcan(wifes car)

Jeff, The car is completely stock to my knowledge aside from a Gillis. 70 something thousand miles. It's done this since I bought it 2 and about 800 miles and 2 years ago. The short rundown is yes to all your questions. Timing belt and all timing has been checked at least 5 times, IAC and EGR cleaned. All that. I've never gotten better than 17", which is why I replaced the lifters in June, replaced a leaky injector and had all 4 cleaned etc. Compression was 160 to 170 across 2 weeks ago. The cam did not look worn to me, but I kind of don't trust my experience on that. I got 17" the last time I ran it before I put in the gasket. Yeah, it's a PITA, but I took my time, and I'm very positive I got the gasket on the lower properly, torqued to 21lbs per Haynes.
When I took the lower off, there was some evidence of a vac leak, so I was confident this would solve my low vac. The shop also said the head facing on the intake was warped a small amount. All I did was remove upper and lower and TB. Had all surfaces except TB reground. Shop said the TB facing was still flat anyway. And somhow the 3/8 metal tube is now leaking.?
I noticed today that when I spray carb cleaner on the IAC itself (not the gasket) that idle gets very slightly more rough. I'm thinking of replacing that next. But it never was touched from before to after!


So, I'll buy the gasket kit one more time and re-do everything I suppose. Now, if I do all the intake gaskets a 2nd time, the only other cause could be my cam, right?? I've tested vacuum with the main supply, and it was at 17 then also (now 15), so I know it's not anything on the tree causing it. Injector o-rings? The guy that cleaned them put all new brown o-rings on them.

For past history on this: http://natoubb.turboford.org/Forum1/HTML/008079.html http://natoubb.turboford.org/Forum1/HTML/008136.html http://natoubb.turboford.org/Forum1/HTML/008412.html

[This message has been edited by Matt S (edited 07-28-2003).]

Jeff, one more question about the plumbing...did you solder the copper, or use threads? Any reason I shouldn't use heater hose? I ask as I had to replace the silicon hoses to the turbo, and there is no one around who carries that size; so I used rubber hose and it seems to be holding fine so far. I need to fix that before anything I guess. Thanks

If the idle changed when you sprayed carb cleaner around the IAC, try changing out the IAC gasket.... might be the source of the vac leak. Also, be sure the TPS is properly seated - could there be a vac leak at the TPS?

Cam: Was there any ridge on the lobes on either side of where the slider rides on it? Did the lobes looks scored at all?

Coolant lines: I used a combination of soldering and compression fittings to fab up my custom turbo cooling lines. I just went thru the plumbing dept at the local hardware store seing what kind of fittings they had to fit my needs. I actually did use fuel line (5/16", I think it was) in a few sections to join the lines together, which lasted 2 years. About a year ago, I replaced the rubber lines with silicone hose for increased reliability.... the rubber lines didnt leak, but after 2 years, they had gotten pretty hard.

------------------
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 20 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 02 Taurus Vulcan(wifes car)

Matt, I'm with Jeff, check out the IAC before redoing the lower intake gasket. Also did you try isolating the leak.

Remove the vacuum feed line from the front upper intake to the vacuum tree. either cap that port or use it to hook your vac gauge to. This takes the vacuum tree and all it's sub systems out of the picture. With your vac gauge hooked directly to the upper intake, does the reading change. If it goes up, then you know the vac tree or a sub-system is leaking. If it doesn't change, then it's related directly to the motor itself - leaking intakes or TB or IAC or PCV system

I'll change the IAC gasket again. I haven't sprayed around the tps yet, I'll try that too. Good thought. The cam lobes didn't have any ridge that I could catch my nail on.
All the lifters looked nice and polished on the right end.

However, there were a few lobes I think that had some brass coloring on the backside of the lobe, near the base of the circle. I have extra gaskets for the tb/upper, so I'll pop the cover and take another look as well.

I have taken vacuum readings directly from the main tree feed. I capped off that port on the tree, but if I'm not mistaken, the turbo fittings have check valves anyway. Can't blow or suck through it. I couldn't blow through the PCV, even pointing my head in the air. Flowed just fine the other way. All the hoses have clamps on them, including a fuel line hose in place of the metal thing on the fpr.

It'll take me another day to get at it. Thanks.