Archived Runaway 1993 12 valve!

[Gizmo 007]

OK fellers, need your help again. Got a '93 dodge with a wicked pump problem.



After starting the truck, it idles like a dream. If i just touch the throttle, it runs away... After restarting, it will idle again, until I touch the throttle. It has the old mechanical rotary pump. Have inspected the boost diaphragm, and found that the pin that rides on the diaphragm shaft (part of the throttle linkage) shoots out when i touch the throttle, but won't retract on it's own.



Does anyone know of anything to look for inside of these pumps that would cause this? could the governor spring be broken and cause this? The problem started instantly while driving, like something inside the pump broke.

Anything is helpful! Thanks!

 

[bmoeller]

Sounds like a governor problem to me.

 

[roadhawg]

I would back the fuel screw out one turn and try it.

I had some experiance with mine running away when trying to get to aggresive with the fuel screw settings.

Hope this helps

Eric

 

[Gizmo 007]

Thanks... will try the fuel screw idea... but if that doesn't solve it... how does one get to the governor?

 

[roadhawg]

Pastor Bob aka bushwacker has posted extensive and detailed info on that very subject in the first gen forum, about the third or forth post down.

Very tricky to follow on some things but if your a determind do it your selfer, you will find many helpfull ideas there.

 

[Gizmo 007]

Well, it's not all candy and roses. Tried the fuel screw, to no avail. Engine still runs away... going to tear into the pump and check the gov. spring. The artical about the gov. spring is great!



Thanks again guys!

 

[rashwor]

I remember...

that some of the early trucks with this style pump had a pin in them that would break and cause a runaway condition like you are describing. There was a recall on my '92 shortly after I bought it (I had 50k miles on it at the time it was recalled) and the fix was to replace the pump. Maybe yours has been afflicted with this.



You might want to check with Dodge on serial numbers of affected trucks / engines. Might be able to check dodgeram.org as some TSBs are shown there. Good luck.

 

[Eric_77]

my 92 had the recall done then a month- 6 weeks later it did the runaway. I would say the fix was not 100% fix. I think the early replacement did not fix the problem as they did something a little different and held on to truck for like a week the second time whereas the first time was a day.