Engine Stuck Wide Open

I recently had my car in for it's first 30,000 service. This weekend out for some spirited driving and the throttle stuck wide open (which I didn't immediately realize) until I changed gears. The revs went to redline and I quickly turned off the key and coasted to the side of the road. After looking at the throttle linkage, I realized that part of the linkage got stuck BEHIND one of the injector lines. I was able to free of the linkage and then drove it home. I was able to duplicate this in the attached two pictures. Has anyone else had this problem? I am worried about trying to bend the line as I know bending hollow tubing is an art. Any suggestions would be greatly appreciated.
Thanks,
Dave
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Since you have the "screw-in" style injector bushing, you may need to also loosen (rotate and then retighten) the line-to-injector connection as well as do a little line bending (rather than just doing it all by bending the line) to get the needed clearance.

 

If I'm not mistaken the throttle body is rotated 90* clockwise from where it should be. the throttle should be under the plenum, it wasn't till the QV that it flipped into that position you have now.

 

+1 Easy fix.

 

Good catch!

Same thing can happen with a carbed engine when you install the hose clamp of the hose going from the left-rear carb to the right rear carb the wrong way. Can catch one of the throttle linkages once you go beyond 80% throttle. Found that one out on a rather congested highway.

Oh, and when you turn off the ignition, don't forget to switch it right back on. You don't want you steering column lock to catch

(See pic: when installed the other way around, facing left rather than right, as on this photo, the bolt of the bottom hose clamp comes dangerously close to the throttle linkage in the bottom of the pic once that linkage is tilting forward, as it does when throttled up )
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QUOTE :Same thing can happen with a carbed engine when you install the hose clamp of the hose going from the left-rear carb to the right rear carb the wrong way. Can catch one of the throttle linkages once you go beyond 80% throttle. Found that one out on a rather congested highway.

I found this two days ago fixing a leaking carb banjo bolt on my GT4. I moved the carb linkage through its range and it hung up on the hose clamp that I had removed and not pointed downward.

 

Correct, the injected cars up to the QV had the throttle linkage on the bottom so this one was installed 90 clockwise. The large idle adjust should be on the right but if yours is on the bottom then you need to rotate the tb 90 degrees anti clockwise. Good catch.

 

His Profile says it is a QV.

 

Then please disregard my advice. It's way past my bed time, sorry.

Alternate theory: perhaps the throttle stop plate got bent towards the fuel line as it appears it is scratching it and looks a little tilted in the bottom picture. Perhaps straightening that a little might correct the situation?

 

Thanks for the advice. I will look at doing both. My concern is the possible over-revved engine. It still seems to run fine so if I bent a valve, would it continue to run so smooth? What are some of the things that could have happened? Spun a bearing on the crank? What do I need to be watching for? I just spent $8,500 on the engine's first major service. I know that seems awfully expensive (it did to me too) but I had a lot of work done including silicon hoses, paint work on the plenum, valve covers, and timing covers, CV boots rebuilt, and new cam shaft pulleys, alternator rebuilt and air box re-stenciled just to name a little.

 

You have to really overrev these engines to hurt them. Even in the Owner's Manual, it mentions to not operate -above- maximum revs for an extended period of time. I've had my 328 GTS to 8,100 RPMS (and it was still pulling hard) with absolutely no issues. (Obviously it wasn't intentional. I was performance testing and my right leg spasmed.)

Luckily, F-cars are not like old British pushrod engines (such as Triumph TR3s or MGAs), where redline is 100 RPMS before starts bending.

 

Thanks Sammy. I was really worried. That was a bunch of money I just spent to have it be all for naught with a engine on the way out.

 

Wow that must have been a bit weird. I remember that I had a similar problem in my old 911. Scared the crap out of me when it happened. It was a pretty easy fix, but still I was glad it did not happen in the middle of a sweeper.

Hopefully no harm done with the over rev and thanks for sharing this. Never know how it might help in the future.

Erik