drastic massive engine power loss, inability to accelerate past 25mph

posting this because it was quite surprising.. what happened was while away on vacation in july a friend was using my car when suddenly the engine started hesitating, he experienced a massive power loss, and the car wouldn't go fast at all, just enough to limp off to the shoulder. it could drive slowly fine, but had no power no acceleration no speed.

turns out he's not fazed by things such as this, he got under the hood and found out it was a leaking vacuum hose elbow connector/enlarger that connects to the throttle body. its related to the MAP sensor so i guess as this rubber connector failed from becoming too brittle the MAP sensor was likely getting false readings and it must have thrown the efi algorithm into confusion, as it would not deliver fuel (well you know what i mean it was doing exactly what its supposed to do but with incorrect MAP data. he jfn (just for now) fixed it using a rubbery gooey heat shrink compound and all was good thereafter, have to wait 2 weeks for a part that probably costs a dollar.

so maybe some of you folks with weird behavior with power loss and hesitation when flooring it at high rpm should inspect these hose connectors, my car is 6 years old. i took a picture of the now epoxied connector (its just right of center beside a larger elbow connector, and it failed on the inside of the elbow, where one wouldn't see) as none of the auto parts stores had anything they could make to replace the original and i don't want to mess around with adding more friction/pressure drop to that hose

I'm having a simalour issue to what you described. Which hoseconnecter are you referring to? The one that goes from the throttle body to the map sensor? Or the hose/connected between the map sensor hose and the big one going to the valve cover?

There's 3 hoses in that general area so it's hard to tell which one your referring to.

There's the Big hose on the left going to the valve cover. One in the middle going the the driver side of the car. And the third hose leading to the map sensor on the right.

Knowing this would help a lot.

Also was the car making a lot more noise when it happened? Like a whoooooop type of sound, almost like a muffler in the front due to the engine misfiring due to the wrong reading to the map sensor.

Hi sorry for late reply - the hose connector that had to be repaired is the one farthest to the right in the picture I took - its very close to the center of the picture, and the hose it attaches to is the one with the 'hook' that is clearly putting some stress on that very hose. If you look really closely in the picture you can see the epoxy on the connector.
I am at best a novice weekend mechanic so I can't supply any advice perhaps some more experienced ppl on the forum can.
Hope you get a diagnosis - post back your results too pls

What your friend encountered was limp home mode. The problem caused the computer to cut power, the problem didn't directly cause the loss in power. So if somebody is having troubles at high rpms I wouldn't suggest what your friend fixed. Always start with easy stuff, air filter, plugs + wires

i think where the loss is, it there is not a hose connector on the one you replaced. But based on your engine design you not only had a vacuum leak, but you lost fuel metering information which is needed to add fuel when you hit the throttle.

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Originally Posted by Pickles

What your friend encountered was limp home mode. The problem caused the computer to cut power, the problem didn't directly cause the loss in power. So if somebody is having troubles at high rpms I wouldn't suggest what your friend fixed. Always start with easy stuff, air filter, plugs + wires

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Thanks for the limp home info, Pickles. While I do agree with what you are saying, I would also suggest that a quick visual inspection of hoses for cracks is part of the 'easy stuff', as in my, or my friends situation, he had this diagnosed in less than 15 minutes right on the side of the road.

I'm not saying you shouldn't check there by any means. However limp mode can be caused by tons and tons of things. In my case it was simply a bad ignition relay

Quote:

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Originally Posted by northguest47

posting this because it was quite surprising.. what happened was while away on vacation in july a friend was using my car when suddenly the engine started hesitating, he experienced a massive power loss, and the car wouldn't go fast at all, just enough to limp off to the shoulder. it could drive slowly fine, but had no power no acceleration no speed.

turns out he's not fazed by things such as this, he got under the hood and found out it was a leaking vacuum hose elbow connector/enlarger that connects to the throttle body. its related to the MAP sensor so i guess as this rubber connector failed from becoming too brittle the MAP sensor was likely getting false readings and it must have thrown the efi algorithm into confusion, as it would not deliver fuel (well you know what i mean it was doing exactly what its supposed to do but with incorrect MAP data. he jfn (just for now) fixed it using a rubbery gooey heat shrink compound and all was good thereafter, have to wait 2 weeks for a part that probably costs a dollar.

so maybe some of you folks with weird behavior with power loss and hesitation when flooring it at high rpm should inspect these hose connectors, my car is 6 years old. i took a picture of the now epoxied connector (its just right of center beside a larger elbow connector, and it failed on the inside of the elbow, where one wouldn't see) as none of the auto parts stores had anything they could make to replace the original and i don't want to mess around with adding more friction/pressure drop to that hose

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I realize I'm bumping an old thread, but does anyone happen to have a part number for this line/elbow? I replaced it once with a dorman elbow but it seems it was too small and cracked again after a couple months from the stress. Thanks!