Contour Enthusiasts Group Archives Forums General Troubleshooting Only at WOT

I have done some searching and think I know what 'maybe' happening, but wanted to make a post and get your opinions as well.

I have a 2k svt w/40k on the clock. Over the past 2-3 weeks the car has developed a sort of hesitation when I drop the hammer. If I run at 3/4 throttle everythings is fine, as soon as I go to WOT the car starts to slow down, almost as if I have hit the fuel cut off, but I could be anywhere in the rpms and it will do the same.

Now I thought that since I was still running on the original plugs that they could be ready for a change. Did that, helped a little (very little) but the hesitation is still there.

OK, I still have the original fuel filter - changed that and it made no difference.

At this point I really don't know for sure what may be causing the problem, I am leaning towards the feul pump - what do you think?

*Remember this is on a returnless and only at WOT

i have the same exact problem... have done the same things as you but also have not changed the fuel pump. Also a '00 with 45k on the clock. Would love to hear if you figure it out.

Sounds like a maf issue. As soon as you clear 60% throttle or so the car goes into closed loop and no longer looks at the O2 sensors for fuel input. Too rich or too lean I can't tell you. Try cleaning it with carb cleaner/brake cleaner or something that evaporates quickly with no residue.

I had a similar problem. I would describe it as a sort of mild & repeating surge. It was so mild I initially figured that it was the character of the car - didn't even know I had a problem.

The surge WENT AWAY when I did a MAF and UIM/LIM cleaning. I don't know for sure which did the trick, but it worked for me.

Good luck & enjoy the ride!

Well I have cleaned the MAF, TB, UIM/LIM and still have the same problem. The car runs better without a doubt since cleaning but when I get on it, it still hesitates. Next I am gunna try new plug wires but after that I am out of ideas, any more suggestions?

Verify your secondaries are opening, first.

Get the plug wires taken care of next, then see what happens.

Pointless to speculate until then.

Steve

No need to verify I can feel them open. Like I said earlier the car runs perfect except when I get on it.

Gunna still give new wires a go though.

As President Reagan said "Trust but verify"

Verify them.

Steve