Show full size 924Board.org
Discussion Forum of 924.org
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 
 Technical FAQ924 FAQ (Technical)   Technical924 Technical Section   Jump to 924.org924.org   Jump to PCA 924 Registry924 Registry

going to rich off the line, can't figure it out.
Goto page 1, 2  Next
 
Post new topic   Reply to topic    924Board.org Forum Index -> 931 Tech.
View previous topic :: View next topic  
Author Message
MikeDanger  



Joined: 21 Nov 2002
Posts: 770
Location: Denver

PostPosted: Sun May 22, 2022 4:13 pm    Post subject: going to rich off the line, can't figure it out. Reply with quote

Hey Guys, got another CIS problem.
So when accelerating it goes to about 10A/F +/-
again, i Have a dual adjustable WUR, and and tried, about 300 settings (I have driven around my neighborhood and pulled over, get out, adjust, drive 100 yards, and repeat 1000 times!)

I have adjusted the pressure correctly and tried variations from there with NO affect.

Basically when I try to accelerate from a stop, it goes way too rich at about a 1/4-1/3 throttle.
Now it starts to come back as the car speeds up,(obviously im backing out of the throttle as the car is accelerating) .
Cruising its ok, but when I go to speed up, it drops.

I set the A/F at idle, both with the Meter mixter screw, and the Allen at the bottom of the WUR.

I just put in a stock non adjustable WUR and it still did the same thing, so Im leaning away from the WUR.



so heres the short list of whats been done related to fuel/intake:

CIS diaphragm replaced
Injectors cleaned and
new fuel filter and pre fuel pump filter
all new silcone vac lines, and intake hoses.
new O2 sensor
new fuel pump.
Rebuilt and modified WUR
_________________
It was either this or a giant box of legos
Back to top
View user's profile Send private message Visit poster's website
MikeDanger  



Joined: 21 Nov 2002
Posts: 770
Location: Denver

PostPosted: Sun May 22, 2022 4:18 pm    Post subject: Reply with quote

Im am i right thinking it can't be a Vac leak, because then it would go lean right??
_________________
It was either this or a giant box of legos
Back to top
View user's profile Send private message Visit poster's website
kondzi  



Joined: 02 Jul 2018
Posts: 485
Location: Poland/EU

PostPosted: Sun May 22, 2022 5:47 pm    Post subject: Reply with quote

Disconnect the vaacum/ boost hose from WUR and see what happens.
The bottom hex screw adjust amount of richness under boost. So first try to sort out when no vaacum / boost condition is applied.
_________________
---
Konrad
'89 951 US
'88 Mustang 5.0 LX Convertible (factory specs)
'84 911 Carrera 3.2 RoW (factory specs)
'81 931 RoW (TBD)
'81 Ford Capri 2.8i (factory specs)
'79 Ford Capri 2.9 (heavily modded)
Back to top
View user's profile Send private message
Fasteddie313  



Joined: 29 Sep 2013
Posts: 2596
Location: MI

PostPosted: Sun May 22, 2022 11:25 pm    Post subject: Reply with quote

When you make an adjustable WUR like that you can push it one way with the screw, but you still have to tap the valve body back the other way don’t you?

Are you doing that?

Moving the valve body in and out of the WUR is what sets control pressure right?
And the installed screw pushes it out so you don’t have to disassemble it every time you want to change it in the out direction..
But to change it back to the in direction, you have to tap it back in with a hammer don’t you?

Moving the valve body out would lessen the tension of the spring on the valve lowering control pressure right?
Tapping it back in would raise control pressure I believe..

Are you confirming your pressure changes with a gauge?
_________________
80 Turbo - Slightly Modified
Back to top
View user's profile Send private message Yahoo Messenger
MikeDanger  



Joined: 21 Nov 2002
Posts: 770
Location: Denver

PostPosted: Mon May 23, 2022 11:17 am    Post subject: Reply with quote

kondzi wrote:
Disconnect the vaacum/ boost hose from WUR and see what happens.
The bottom hex screw adjust amount of richness under boost. So first try to sort out when no vaacum / boost condition is applied.


already did that.

Actually no the hex screw doesnt really do that. That is controlled by the large diameter spring under the diaphragm

the hex screw adjusts the WARM control pressure.
_________________
It was either this or a giant box of legos
Back to top
View user's profile Send private message Visit poster's website
MikeDanger  



Joined: 21 Nov 2002
Posts: 770
Location: Denver

PostPosted: Mon May 23, 2022 11:22 am    Post subject: Reply with quote

Fasteddie313 wrote:
When you make an adjustable WUR like that you can push it one way with the screw, but you still have to tap the valve body back the other way don’t you?

Are you doing that?

Moving the valve body in and out of the WUR is what sets control pressure right?
And the installed screw pushes it out so you don’t have to disassemble it every time you want to change it in the out direction..
But to change it back to the in direction, you have to tap it back in with a hammer don’t you?

Moving the valve body out would lessen the tension of the spring on the valve lowering control pressure right?
Tapping it back in would raise control pressure I believe..

Are you confirming your pressure changes with a gauge?


No you dont have to tap the valve body, if you use the hex scew on the bottom. I can fully control the Warm pressure with that.

yes of course I have a gauge, as mentioned in the list.
_________________
It was either this or a giant box of legos
Back to top
View user's profile Send private message Visit poster's website
Fasteddie313  



Joined: 29 Sep 2013
Posts: 2596
Location: MI

PostPosted: Mon May 23, 2022 11:24 am    Post subject: Reply with quote

Must be a different WUR mod than I am thinking then..
_________________
80 Turbo - Slightly Modified
Back to top
View user's profile Send private message Yahoo Messenger
MikeDanger  



Joined: 21 Nov 2002
Posts: 770
Location: Denver

PostPosted: Mon May 23, 2022 1:47 pm    Post subject: Reply with quote


_________________
It was either this or a giant box of legos
Back to top
View user's profile Send private message Visit poster's website
kondzi  



Joined: 02 Jul 2018
Posts: 485
Location: Poland/EU

PostPosted: Mon May 23, 2022 4:36 pm    Post subject: Reply with quote

I think you’re doing it wrong. Take a look at the diagram of WUR and try to understand the physics / forces / tensions on internal parts. Moving the round blocks in and out of the WUR body is affecting the pressures. One affects the other, the other does not affect the first. Then add to that the hex screw at bottom, which IS FOR LIMITING RICHNESS UNDER BOOST. Hook up pressure tester and push in / out the blocks. Set it to the values from Service manual. Then add vaacum / boost with a pump / syrgine and check on the pressure tester how it’s affecting the pressures.

EDIT: see my thread for manual control pressures.
https://www.924board.org/viewtopic.php?t=43790&postdays=0&postorder=asc&start=15
_________________
---
Konrad
'89 951 US
'88 Mustang 5.0 LX Convertible (factory specs)
'84 911 Carrera 3.2 RoW (factory specs)
'81 931 RoW (TBD)
'81 Ford Capri 2.8i (factory specs)
'79 Ford Capri 2.9 (heavily modded)
Back to top
View user's profile Send private message
MikeDanger  



Joined: 21 Nov 2002
Posts: 770
Location: Denver

PostPosted: Tue May 24, 2022 6:14 pm    Post subject: Reply with quote

Im pretty sure its NOT the WUR. I can make the car very lean (warm or cold) and it still goes to 10A/F when accelerating, gong to or above 3k

the vac line to the WUR is disconnected, again NO difference.

what else would make it go rich??

what if the decel valve was bad?

this is sort of the opposite of a Vac leak.
_________________
It was either this or a giant box of legos
Back to top
View user's profile Send private message Visit poster's website
Fasteddie313  



Joined: 29 Sep 2013
Posts: 2596
Location: MI

PostPosted: Tue May 24, 2022 9:57 pm    Post subject: Reply with quote

Boost leak would make it go rich just as you say..
The opposite of a vacuum leak..

Decel valve only if it was leaking to atmosphere..
_________________
80 Turbo - Slightly Modified
Back to top
View user's profile Send private message Yahoo Messenger
MikeDanger  



Joined: 21 Nov 2002
Posts: 770
Location: Denver

PostPosted: Thu May 26, 2022 2:42 am    Post subject: Reply with quote

well... maybe a clue?
I talked to a local shop... and he mentioned how I should set the idle A/F with the O2 disconnected.

So I did that. initial start up was at 11.6, where it pretty much stayed. so I adjusted at the distributor/meter to 14.5.
Now when I rev the engine it only goes to 12.5 (in the garage, havent driven yet).

So what does that say?? couldn't burn out a new o2 sensor in 20 miles could I?
_________________
It was either this or a giant box of legos
Back to top
View user's profile Send private message Visit poster's website
Fasteddie313  



Joined: 29 Sep 2013
Posts: 2596
Location: MI

PostPosted: Thu May 26, 2022 3:10 am    Post subject: Reply with quote

He is right..
Or set it with the dwell meter method..

That means you has the AFR screw set way too rich for its standard base tune..
_________________
80 Turbo - Slightly Modified
Back to top
View user's profile Send private message Yahoo Messenger
MikeDanger  



Joined: 21 Nov 2002
Posts: 770
Location: Denver

PostPosted: Thu May 26, 2022 8:40 am    Post subject: Reply with quote

Fasteddie313 wrote:
He is right..
Or set it with the dwell meter method..

That means you has the AFR screw set way too rich for its standard base tune..


it was only a quarter turn to get it to 14.5
_________________
It was either this or a giant box of legos
Back to top
View user's profile Send private message Visit poster's website
MikeDanger  



Joined: 21 Nov 2002
Posts: 770
Location: Denver

PostPosted: Fri May 27, 2022 4:20 pm    Post subject: Reply with quote

was doing a bit of reading on o2 sensors, saying the need outside refernce air, amont other things.... so I decided to get under and have a look just to see whats what.
and I find the outside of the sensor is covered in oil. oil seems to be leaking right on to it. and the end where the wire goes in, has drops of oil on it (rather than just a thin coating.) could oil have gotten IN TO the sensor??

I pulled out the sensor it has a coating of soot on it, but I assume that from running rich, im sure there is slight oil burn, but it can't be bad enough to kill a new sensor in less than 50 miles.


_________________
It was either this or a giant box of legos
Back to top
View user's profile Send private message Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    924Board.org Forum Index -> 931 Tech. All times are GMT + 10 Hours
Goto page 1, 2  Next
Page 1 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group