engine cuts out when supercharger engages

eeh69

Registered User
anytime i run the supercharger past 0 on the gauge it cuts off (kind of bucking) in any gear. many new parts tryin to get it to run perfect but no luck. also it doesnt seem to have the power the old motor did after it broke a rod.
any help will be appreciated
 
When that happened to me, I sprayed the Air Bypass butterfly (behind the supercharger) with WD40 and it solved the bucking problem. Good luck
 
parts replaced

off the top of my head..... Electronic Module, coil pack, plugs, wires, cam sensor, crank sensor. i know im forgetting something but thats it for now.

I was told that maybe my fuel pump isnt pumping enough fuel when its engaged... any thoughts?

also the old motor did this,, then when i replaced it it didnt do it for about a month and half. now its back.
 
cutting out

I've got the same problem. I've had it for two years.
I've basically changed the parts you have...plus o2 sensors,
motor mounts, tps+ maf sensor.
I'm in the process of trying to get a cheap computer.
Do me a favor?
Put a timing light on it....watch the light.....rev the motor
and see if the light stops blinking.
That is the case with mine....proving to me that it's a weak
spark as the rpm climb. Same thing with several other I've talked to. What's causing it, I'm not sure.
Good luck

Tom
 
If you are worried about fuel pressure, then buy a fuel pressure guage and hook it up to the Shraeder Valve next to the SC. Most of them you can leave hooked up. and take the car out for a spin and note the pressure as you hit boost. A weak pump or pressre should be obvious. If not then you can rule out the pressure/pump. Sounds like bad wires, but your sure they are good? Most people and myself have had probs with bucking/missing at boost turned out to be bad wires/plugs.
 
Strange.

I've had this prob on both my sc and my old xr7. On the SC, the hose clamp that connects to the bypass valve mysteriously came outward, thus, causing the valve to get stuck and making the car run n/a. At first, I figured my blower had seized. Took me about a day of looking to notice it. On my old xr7, I had defective plug wires which caused a bucking condition under boost conditions. Also, on the SC, I used some Bosch plugs and experienced the same thing, bucking under boost.
 
i got the wires recently i beleive theyre magna tech, plugs also new and are motorcraft.

today i took the belt running the supercharger and it dont buck...still not a lot of power but it dont buck.
 
I'm currently having the same problem, seems like alot of SC's are. Mines going to the garage to get checked for vacume leaks. Because if it was the plugs or wires ( which are new from SC Performance.com installed by Ford) wouldn't it buck or miss all the time.
I'll post again on Thursday with results of the test and other possibilities.

Please keeps this going 'till it's solved
Thanx
Mark.
 
Cutting out

I don't believe the vacuum leak theory.....at least not in my case.
The only possibility that I could think of is leaks around the intercooler. (which I don't have)

It is a textbook case for 'misfires under load' which is what people seem to be describing. It usually points to an ignition problem. (plugs-wires ect)

Can anybody humor me and put a timing light on it.....rev it past 2000 and watch to see if the light stops blinking.
That's what my case is...which says weak spark. I'm still working on it.
Let me know

Thanx
Tom
 
Tganley....Are your parts new?

DIS good? Got heat sink under it? Good wiring from DIS to the coil? And most overlooked - CORRECT order for your plugs? Have you ran any codes?
 
Yes if the timing light stops lighting when you rev the engine you are loosing spark. Of course it could be the plug or the wire on that cylinder as well causing the problem. After eleminating those 2 items take a look at the coil and associated wiring, if these things check out OK take a look at the DIS module and wiring.
 
misfires

All parts were new...and motorcraft.
Grounds, wiring, and supply voltage all good.
(coilpack-dis mod-eec)
A set of new plugs cures the problem for a month or
so.
It's a weak spark for sure. (all plugs)
I'm just wondering who with the same symptoms
has the same problem.
 
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