I'm ecstatic!!! - Vacuum problem solved!!! Question too.

2FastLX · 09-19-2001, 03:41 AM

All this time and all the trouble I have been having diagnosing a vacuum problem is finally over. I replaced my throttle body tonight with an Accufab 70mm and EGR spacer and I now have tons of vacuum! I no longer have a surging idle problem, no more bucking and surging below 1500rpm while driving, and it accelerates smoother than ever. The car runs better than it ever has and I had a smile on my face all the way home.

Now for the question...
I have noticed the throttle likes to hang a bit and even climb a little when I let off the gas to shift. It doesn't feel like the TB is sticking, but more like a weak throttle return spring. I noticed it when I set the TPS. After getting it to .98 volts and opening the throttle and letting it return to the stop my reading went from .98 to 1.01 volts. I reset it and bumped the throttle a few times and got a different reading every time varying from .93 to .98. That's with a new TPS too. Any thoughts?

------------------
Gunning for 12's!

Buy your parts here
ICQ# 42269241

WADS56 · 09-19-2001, 04:46 AM

I had the same problem with my Accufab. This is what I did but it is hard to explain. The spot where the throtal cable mounts to that bracket thing by the throtalbody is what the problem was. I moved the cable to the front of the bracket so when the throtal would close it would be real tight. It binds the cable a litle bit when the throtal is closed making sure it can't open unless you step on the gas. Hope this helps.

Are you still going to do the 351 now?

------------------
79 hatch w/ NA 347,stage 2 Canfield heads, out of the box Victor 5.0 intake, solid roller cam, Aeromotive fuel system, proshifted TKO II.MY CAR http://www.mustangworks.com/cgi-bin/...splay.cgi?1288
93lx all stock + tremec

2FastLX · 09-19-2001, 05:07 AM

I am still going to build a 351, but the hole reasoning behind doing so was because I was sick and tired of chasing the problem I had with this one after all the mods. I'm looking for a 91-93 notchback now to drop this engine into for a street car and I'm going to build up a 393 stroker to put in my current Stang and use it for a drag toy.

Speaking of drag racing, watch for an update soon Wade for another rental at US41. We're going to be planning one last big hurrah for this yeah in the next few weeks. You still owe me that ride too!

If we get to the track again soon you can show me what you mean there. It may not work because I had to cut my throttle cable bracket down to clear my valve covers, but we'll see.

------------------
Gunning for 12's!

Buy your parts here
ICQ# 42269241

[This message has been edited by 2FastLX (edited 09-19-2001).]

WADS56 · 09-19-2001, 06:48 AM

That will be cool if you guys have another meet. Me and a few of my frinds could make it for sure. I need some good track time so I can dial in my new clutch (long style). I am N.A. now so it won't be as fast, but it will pull a 1.4 60ft so that should be fun if you want to go.

As for the bracket thing, I'm talking about the spot where the throtal cable screws into it. I moved it on the other side and it worked great. You have to have it mounted to somthing or your throtal would not work at all.

2FastLX · 09-19-2001, 10:20 AM

Ok, I might know what you're talking about now.

I was going to see if I could take the spring off of my old TB and put on it and see if that made a difference. You can tell it has a lot stronger spring on it.

------------------
Gunning for 12's!

Buy your parts here
ICQ# 42269241

09-19-2001, 03:41 AM	#1
2FastLX The Photoshop Guru Join Date: Feb 2001 Location: Mecca, Indiana Posts: 1,419	I'm ecstatic!!! - Vacuum problem solved!!! Question too. All this time and all the trouble I have been having diagnosing a vacuum problem is finally over. I replaced my throttle body tonight with an Accufab 70mm and EGR spacer and I now have tons of vacuum! I no longer have a surging idle problem, no more bucking and surging below 1500rpm while driving, and it accelerates smoother than ever. The car runs better than it ever has and I had a smile on my face all the way home. Now for the question... I have noticed the throttle likes to hang a bit and even climb a little when I let off the gas to shift. It doesn't feel like the TB is sticking, but more like a weak throttle return spring. I noticed it when I set the TPS. After getting it to .98 volts and opening the throttle and letting it return to the stop my reading went from .98 to 1.01 volts. I reset it and bumped the throttle a few times and got a different reading every time varying from .93 to .98. That's with a new TPS too. Any thoughts? ------------------ Gunning for 12's! Buy your parts here ICQ# 42269241

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09-19-2001, 04:46 AM	#2
WADS56 gear banger Join Date: Aug 2000 Location: CHICAGO Posts: 1,144	I had the same problem with my Accufab. This is what I did but it is hard to explain. The spot where the throtal cable mounts to that bracket thing by the throtalbody is what the problem was. I moved the cable to the front of the bracket so when the throtal would close it would be real tight. It binds the cable a litle bit when the throtal is closed making sure it can't open unless you step on the gas. Hope this helps. Are you still going to do the 351 now? ------------------ 79 hatch w/ NA 347,stage 2 Canfield heads, out of the box Victor 5.0 intake, solid roller cam, Aeromotive fuel system, proshifted TKO II.MY CAR http://www.mustangworks.com/cgi-bin/...splay.cgi?1288 93lx all stock + tremec

09-19-2001, 05:07 AM	#3
2FastLX The Photoshop Guru Join Date: Feb 2001 Location: Mecca, Indiana Posts: 1,419	I am still going to build a 351, but the hole reasoning behind doing so was because I was sick and tired of chasing the problem I had with this one after all the mods. I'm looking for a 91-93 notchback now to drop this engine into for a street car and I'm going to build up a 393 stroker to put in my current Stang and use it for a drag toy. Speaking of drag racing, watch for an update soon Wade for another rental at US41. We're going to be planning one last big hurrah for this yeah in the next few weeks. You still owe me that ride too! If we get to the track again soon you can show me what you mean there. It may not work because I had to cut my throttle cable bracket down to clear my valve covers, but we'll see. ------------------ Gunning for 12's! Buy your parts here ICQ# 42269241 [This message has been edited by 2FastLX (edited 09-19-2001).]

09-19-2001, 06:48 AM	#4
WADS56 gear banger Join Date: Aug 2000 Location: CHICAGO Posts: 1,144	That will be cool if you guys have another meet. Me and a few of my frinds could make it for sure. I need some good track time so I can dial in my new clutch (long style). I am N.A. now so it won't be as fast, but it will pull a 1.4 60ft so that should be fun if you want to go. As for the bracket thing, I'm talking about the spot where the throtal cable screws into it. I moved it on the other side and it worked great. You have to have it mounted to somthing or your throtal would not work at all.

09-19-2001, 10:20 AM	#5
2FastLX The Photoshop Guru Join Date: Feb 2001 Location: Mecca, Indiana Posts: 1,419	Ok, I might know what you're talking about now. I was going to see if I could take the spring off of my old TB and put on it and see if that made a difference. You can tell it has a lot stronger spring on it. ------------------ Gunning for 12's! Buy your parts here ICQ# 42269241