Car runs great when cruising but breaks down under torque??


Asked by Aug 21, 2013 at 06:53 AM about the 1974 Triumph TR6

Question type: Maintenance & Repair

6 Answers

Not enough fuel....the diaphragm in the fuel pump is compromised, fuel filter is obstructed or rust in the tank is preventing normal fuel flow~

Best Answer Mark helpful

is this fuel injected or does it have SUs? Been so long, I forgot- I'm guessin' SUs cause if it is Lucas fuel injection, you really got a problem- first suggestion is to find a really good classic car mechanic like my friend Steve here in Santa Fe- really, he has his own shop and only works on them one at a time- a beautiful car like yours needs special attention to keep it running right- not the "assembly line" procedure of ordinary garages, as good as they may be- I think the judge is right though, it's probably fuel- specific suggestions: check the fuel filter, fuel lines, gas tank for dirt and rust- do you know if the gas tank is clean, or new replacement? Man, a 100 year old gas tank is no good and it is where you should start- also, replace those SUs with Webers- get somebody good to do it, like I said

1 people found this helpful.

Check the distributor breaker plate, make sure it isn't pulling sideways when the vacuum advance pulls it, this will cause a change in the dwell that will lead to poor performance. Also change out the condenser.

2 people found this helpful.

Usually a misfire under load points to the ignition system. I'd start there first then, if no improvement, check the fuel system. HTH. -Jim


I found the problem to be in the gas. The car sat for a couple years so I think I picked up something in the tank. I added Seefoam to a full tank and it cleared up.

4 people found this helpful.

Awesome, thanks for letting us know! Glad you got it fixed! -Jim

1 people found this helpful.

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