Drivetrain 91 5.0 Stalls When I Try To Shift Gears

[Cmov]

I have a problem with my 1991 Mustang gt, the car runs great but when I take it out of gear and leave it in neutral to stop the car, it stalls on me. It does not stall on idle if the car is at a stopped. I have changed the idle air control to 3 different brands ( ford, discount auto parts and napa). the computer is giving no codes, it was recently remanufactured. The engine was rebuilt on december 2011 and the problems did not start until june of 2012. I have taken it to 4 mechanics and the car is at the ford dealer now, no one seems to find anything wrong with the car. Anyone with any ideas please comment i will take any suggestions at this point.

the mods are: Trickflow Track top end kit, 24lb fuel injectors and mass air flow to match the 24lb, bbk long tube headers, bbk x-pipe catted, 3:73 gears, 190lph fuel pump, new spark plugs.
Link to trickflow top end kit : http://www.trickflow.com/partdetail.asp?part=TFS-K514-360350B&autoview=sku​

 

[50FoxBodyGT]

aod or 5spd?

 

[ratio411]

Brake booster diaphram leaking vacuum when you push the brakes?

Just a thought.

There is another simple item that causes this, but I can't remember what it was...
I'll probably kick myself when I do, it's something very simple.

 

[srtthis]

shift faster ? lol

 

[Mike86Stang]

Id say reset your idle air adjustment, sounds like its too low. If not I'd start looking for vacuum leaks.

 

[sd331]

sounds like your vss ( vehicle speed sensor) in the tranny is bad

 

[Mike86Stang]

sounds like your vss ( vehicle speed sensor) in the tranny is bad

That's not necessarily true.. the vss does help the computer control fuel enrichment and indicates load, but my car is supposed to have a vss but i never installed one ( MAF swap EEC) and I do not have this problem.

 

[sd331]

That's not necessarily true.. the vss does help the computer control fuel enrichment and indicates load, but my car is supposed to have a vss but i never installed one ( MAF swap EEC) and I do not have this problem.

the vss tells the computer when the car is speeding up and slowing down. if you switched to maf from sd and it works good for, thats great, sometimes people get lucky, but you cant say 'if i dont have one so you dont need one' is not correct, do a search on vss and stalling then get back to me. the op said it idles good w/ no problems only when its in neutral and coming to a stop. so doing an 'idle air adjustment' ( i guess u meant reset the idle) isnt going to solve his problem

 

[Mike86Stang]

the vss tells the computer when the car is speeding up and slowing down.

Yes, the vss sends a signal to the EEC to help the computer infer/ determine load.

you cant say 'if i dont have one so you dont need one' is not correct

This is a fair statement, some EEC's are more finicky/ sensitive than others to these things due to the different programs.

do a search on vss and stalling then get back to me. the op said it idles good w/ no problems only when its in neutral and coming to a stop. so doing an 'idle air adjustment' ( i guess u meant reset the idle) isnt going to solve his problem

I'm not doing a search on vss and stalling, I've been doing this long enough and know all to well how the EEC system works. If his idle air adjustment (base idle settling) is incorrect or set too low yes he will stall coming off accel/ decel when coming to a stop b/c his vacuum won't be where it is supposed to be.Can the vss cause the stalling to, yeah it could but it is not the only answer.

 

[ratio411]

sounds like your vss ( vehicle speed sensor) in the tranny is bad

BAM!
That's the 'simple' problem I was talking about!
It doesn't affect every vehicle the same way, but this is one of the possible symptoms.

 

[sd331]

I'm not doing a search on vss and stalling, I've been doing this long enough and know all to well how the EEC system works. If his idle air adjustment (base idle settling) is incorrect or set too low yes he will stall coming off accel/ decel when coming to a stop b/c his vacuum won't be where it is supposed to be.Can the vss cause the stalling to, yeah it could but it is not the only answer.[/quote].
i wasnt saying it was the only answer, the guy was looking 4 some help & i threw an idea out there & you shot it down & now you say the vss can cause that problem ( i think you did a search). so please in the future dont shoot op ideas down unless ur 100% sure. and 'idle air adjustments' are for carburetors not for efi. the correct terms used are base idle reset or resetting the idle

 

[Mike86Stang]

i wasnt saying it was the only answer, the guy was looking 4 some help & i threw an idea out there & you shot it down & now you say the vss can cause that problem ( i think you did a search). so please in the future dont shoot op ideas down unless ur 100% sure. and 'idle air adjustments' are for carburetors not for efi. the correct terms used are base idle reset or resetting the idle

You need to read more thoroughly... I said that it wasn't necessarily true that the vss had to be bad. I didn't "shoot down" your idea. I guess I must have hurt your feelings...

I don't need to do a search..and frankly I don't give a crap what you think. Look at my post count and when I became a member.. im no spring chicken when it comes to mustangs Im not saying I know it all but I've learned and read and been through enough on my own to know without having to do a search on stangnet or any other search engine for an answer about something as simple as this.The bottom line is that there is not, just 1 possible answer to his issue.

If your stubborn enough to get hung up on the semantics of base idle reset or an idle air adjustment that tells me exactly the kind of person you are. Seems to me that you feel like you have something to prove since i "shot down your idea" and you have to prove some sort of a point. Whatever....

 

[sd331]

You need to read more thoroughly... I said that it wasn't necessarily true that the vss had to be bad. I didn't "shoot down" your idea. I guess I must have hurt your feelings...

I don't need to do a search..and frankly I don't give a crap what you think. Look at my post count and when I became a member.. im no spring chicken when it comes to mustangs Im not saying I know it all but I've learned and read and been through enough on my own to know without having to do a search on stangnet or any other search engine for an answer about something as simple as this.The bottom line is that there is not, just 1 possible answer to his issue.

If your stubborn enough to get hung up on the semantics of base idle reset or an idle air adjustment that tells me exactly the kind of person you are. Seems to me that you feel like you have something to prove since i "shot down your idea" and you have to prove some sort of a point. Whatever....

lol, listen u didnt hurt my feelings or ego, i cant stand people like you that think they know it all and have to put there 2 cents in when they shouldnt, i could have jumped on your 1st post of 'idle air adjustment'? and tell u your saying it wrong but i didnt . your right there is no 1 possible answer, so when op give ideas or help dont tell people that 'it wasnt necessarily true' when in fact it could be, and using the wrong terminology of 'idle air adjustment' ? and 'base idle settling' ? (???) will have op scratching there heads wondering what you mean. 10,333 posts in 12 yrs is impressive, that puts you at about 3 posts a day everyday for 12 years. there is another life out there. im done with this. i hope cmov finds out whats wrong w/ his car and gets it fixed