A taste of whats coming...

[Randomrage]

are you using a missing lind or fcd? my guess is that at 65 mph you are at like 0 or 1 psi on your boost gauge. am i right?

A missing link. Think its that? Doesnt seem to have problems going from vac to boost when accelerating.

I also found a boost leak, at the manifold to turbo gasket. Either that copper gasket is bad, or the manifold flange is warped slightly. The leak gets quieter as the car warms up.

Help!

Edit! Looked at the Missing Link, there is a hole in one side of it. Isnt there supposed to be a filter there?

 

[VelocitàPaola]

Edit! Looked at the Missing Link, there is a hole in one side of it. Isnt there supposed to be a filter there?

Yep. Without it, you're just creating a vac leak for your car. Sorry I can't help more, but I haven't seen any place to buy just the filters. I know of people that either packed it with cotton or used a filter from a cigarette, though.

 

[cs82685]

Ok, now its right off the intake manifold, and that made the fluttering go away completely, thanks.

Here's whats going on:
1.) Bucks and stumbles while going down the road at ~65mph.
2.) Whered all my vacuum go? SAFC says I have around 88mmhg of vacuum at idle, I used to have down in the 400s before I belive. Not sure. Anyway, it reads about 15 on the boost gauge at idle.
3.) The narrowband a/f gauge I bought (like a moron), what the heck. A red light and three amber lights sit on "Lean" at idle while a green light is simultaneously over at "Rich."
4.) Still dies at stops.

I'm not much help with this other stuff but I was just wondering if this is how you had your vac setup.

"well after my failed attempt to install a sfmu(broken used pos) i had to reinstall my fmu and run that long vac line. last time i used a tee that was allready there. it went to the vac line going to the ac compressor. not knowing anybetter my fuel pressure under boost(8.7psi) would peg and it took it awhile to get back to normal(55 psi) well that so called tee has a check valve in it. so i changed my vaccum setup and man can i tell a big difference. my car actually feels fast now. and the fuel pressure after boost immediately drops to 55 psi. i haven't had a chance to log my afrs yet but my wideband xm-1 looked good from what i could tell between watching all my gauges and the road. so to make a long story short dont use that thing as a tee for nothing."

Yep. Without it, you're just creating a vac leak for your car. Sorry I can't help more, but I haven't seen any place to buy just the filters. I know of people that either packed it with cotton or used a filter from a cigarette, though.

^^^I've heard of this too, I'd say easiest and cheapest attempt at getting this figured out is to stick some sort of filter in there

 

[Randomrage]

What about just covering the hole up? That helped the idle when I put my finger over it. And how would I get something to stay in the little bitty hole anyway?

 

[VelocitàPaola]

I don't have a missing link, so somebody correct me if I'm wrong, but if you just cover up the hole, wouldn't that defeat the point?

I would try packing something in there with a Q-tip or a toothpick.

 

[Randomrage]

I don't have a missing link, so somebody correct me if I'm wrong, but if you just cover up the hole, wouldn't that defeat the point?

I would try packing something in there with a Q-tip or a toothpick.

AFAIK the early MLs didnt have a hole. Ill give that a shot when I find something suitable.

 

[VelocitàPaola]

The filter in the later model MLs is there to bleed off air going to the MAP so it doesn't see positive pressure. If you cover it completely, the MAP will see boost, and you'll see fuel cut.

The early model ones didn't have a filter, but they still had a hole (albeit a much smaller hole) that served the same purpose - to bleed off pressure.

Just thought I'd share what a little research did for me.

In any case, don't cover it, look for something to restrict air flow, but not completely stop it (i.e. cotton or something).

 

[Randomrage]

Ok, did that. Now Im getting about -20 on the boost gauge, and -360 on the SAFC. Nice. Idles a lot better now. Also runs more smoothly at 65mph, thanks guys!

Still wants to stall when coming to a stop though, and the car bogs when I hit boost. Any ideas?

 

[VelocitàPaola]

The only thing I can think of is the fuel system. What do you have in there so far? The SAFC-II, Walbro 255, 12:1 FMU, and stock fuel injectors, right?

Make sure the FMU is hooked up properly. Other than that, I'm almost wondering if the SAFC-II is screwing something up. If it's easy to do, disconnect the power wire to the unit. Then do disconnect the MAP interruption, before reconnecting it to it's original configuration. Perhaps it may fix things until you can configure the SAFC better.

Also, you might want to look into that exhaust leak. Confirm that it is actually occuring.

 

[Randomrage]

The only thing I can think of is the fuel system. What do you have in there so far? The SAFC-II, Walbro 255, 12:1 FMU, and stock fuel injectors, right?

Correct. Do you think its running rich or lean?

Make sure the FMU is hooked up properly.

Ill check that out tomorrow when daylight gets back. Getting cold out there too haha!

Other than that, I'm almost wondering if the SAFC-II is screwing something up. If it's easy to do, disconnect the power wire to the unit. Then do disconnect the MAP interruption, before reconnecting it to it's original configuration. Perhaps it may fix things until you can configure the SAFC better.

Worth a try. Thanks!

 

[VelocitàPaola]

By the sound of it, it almost sounds like your experiencing something similar to fuel cut (if not fuel cut itself) - so I'd say you're running lean.

 

[DSMcrazy3]

Get that manifold flange fixed asap. With that hot exhaust getting by that gasket will eventually burn it up and even a flat non-warped flange will be pointeless since those runners won't be sealed off, allowing more and more to burn.

This will cause you to have..I guess you could call it turbo lag...I learned the hard way. 6 psi and 6k rpms Lol

 

[Randomrage]

Get that manifold flange fixed asap.

Will do. I wont be doing much boosting till I take this thing down to the local turbo shop and get a wideband dyno tune put on it next Saturday or so.

This is an odd question, but what would occur if I had somehow managed to hook the fmu lines up backwards?

 

[Livid]

The bottom line of the fmu is the return line to the tank and the side is to the fuel rail. Just trace them back it's not to hard. Also you might want to check your idle fuel pressure.

 

[VelocitàPaola]

Just to help you visualize the set up...

You must be logged in to view this image or video.

 

[selmerguy]

if you want a easy filter for yout ml lift up your back seat and steal some foam. i have been using it for awhile and no problems.

hooking your fmu up backwards would cause you to run rich and idle/run bad. lots of black smoke.

 

[Randomrage]

Im doing the good ol' work-n-lurk right now.

Anyways, while browsing/searching about, I ran across this in another thread:

I run an SAFC2 on my car so I didn't opt to go for the missinglink, however my car runs fine. ..
The reason I say this is because if your planning on tuning with an SAFC, you might have to scrap the missing link idea because reports say "they don't work together" But some people say they do.

Im running a SAFCII and an ML. How can I get rid of the ML, and just use the SAFC to keep the map sensor from seeing positive pressure?

 

[selmerguy]

Im doing the good ol' work-n-lurk right now.

Anyways, while browsing/searching about, I ran across this in another thread:


Im running a SAFCII and an ML. How can I get rid of the ML, and just use the SAFC to keep the map sensor from seeing positive pressure?

you cant. i ran the ml and the safc2 with no problems. and the safc is worthless for our cars. the safc just changes the map voltage to adjust fuel. it wont stop it from seeing boost. your problem is the filter not being in your ml. you should hear it as soon as you open the hood.

 

[redeclipse7782]

That fuel setup diagram is wrong. First off you dont use the stock fpr with the sfmu, you remove it. Secondly the reture line is not on the same side as the feed on the fuel rail. Here is a diagram I made a few months back when I was doing my fuel system. It also includes all part numbers and where to buy the parts.
http://www.dsmtuners.com/forums/attachment.php?attachmentid=48906&d=1111584972

 

[VelocitàPaola]

First off you dont use the stock fpr with the sfmu, you remove it.

He has an FMU, he needs the stock FPR...

Secondly the reture line is not on the same side as the feed on the fuel rail.

It's a schematic, sue me.

 

[Randomrage]

Yeah, missing link is fixed, as far as I can tell. Doesnt bog as easily at stoplights, but it still does it occasionally. And Im still getting mad hesitation at -10 on the gauge, if Im easing into it.

Im taking it down to the TurboTune in G-boro next Wednesday and let them do their wideband tune thing. Then Im getting a real a/f gauge, and a fuel pressure gauge.

Thanks a million for the help guys. Ill post an update next Wednesday, if not before, and hopefully a dyno sheet soon after that.

Edit: Yo, is it always like this? You know, the first time?

 

[XMasta19]

The diagram for the 95-96 early fuel system looks just right to me. I've got one, and I think it's possible that my stock fpr is on one side, with the return/supply lines coming off the other. The FMU setup looks right as well considering the SFMU was not even mentioned as previously stated. Good luck with that dyno tune, let us know how it goes.

 

[Randomrage]

Good luck with that dyno tune, let us know how it goes.

Thanks dude, I appreciate it. Im at my wits end (and possibly mechanical skills end) on this. I cant wait to get her running right.

 

[DSMcrazy3]

Did you get the flange fixed yet? I wouldn't dyno-tune until everything that you can fix is fixed...Seriously...

 

[DSMcrazy3]

The diagram for the 95-96 early fuel system looks just right to me..

Agreed good job Velocità.

I've got one, and I think it's possible that my stock fpr is on one side, with the return/supply lines coming off the other. The FMU setup looks right as well

I too have a 95, and on mine, the feed and return line both attatch on one, with the FPR on the other