Help needed!! Car cuts out at higher RPM

[axelnut1]

Well the car has been running great until yesterday. At idle and normal driving it is fine. When you nail the gas in 1st, 2nd, or 3rd gear the motor cuts out. Almost like it is hitting a rev limiter. TPS is set, maf was already clocked long before the problem. Still have the problem with the spout plug unplugged. You can rev it in netural it is fine and with the clutch pushed in it revs. fine. Normal driving it is fine. car was running fine and all of a sudden this started happening. Thanks in advance for any help. Here is a list of what's on the car.
'88Gt Mass Air Converted, Ford Racing Long Block, Trick Flow Intake, BBk 70mm Thorttle Body, 75 MM Mass Air Flow Meter, Ford B-cam, GT-40X Heads, 30lb. Injectors, 190 lph Fuel Pump, Sumit Racing Ceramic Coated Headers, Aluminum Radiator w/ Electric fan, no smog pump or A/C, Ford Racing 9mm plug wires, MSD Digital 6 Ingnition Box, MSD Blaster Coil, BBK Adjustable Fuel Pressure Regulator, Mac Cold Air Intake, Power Master alt., AGR Power Steering Pump. Custom rear seat delete, Laural Mountain Sub Frame Connectors, 4:10 gears.

 

[axelnut1]

Some more info

Sorry, forgot to add this. This problem happens with the engine warm or cold.

 

[importhater5.0]

i had the same problem with my 90 Notchback. THe car ran fine at lower rpm, cold, hot, raining, whatever. BUt i would rev up to over 3500rpm, and it would just break up and carry on. I checked everything possible, MAF, TPS, coil, plugs, wires , Air idle sensor, and so on. wasnt any of them. i asked my dads one friend who owns and operates a mechanic shop and he said it sounded like a relay problem. So i just started replacing the relays for the fuel injection and a bunch of other ones. THere are a couple relays down in the passengers side kick panel above the ECM. I replaced those and still had nothing! same F'n problem! So i crumbled and took it to my buddys friend who is a master tech at a Ford dealership and specializes in electrical work. He went over the whole wiring harness in the car and it came down to the F'n relay that i had already replaced! THe one that i replaced it with was faulty, a brand new one, go figure! so he put in a MOTORCRAFT replacement and the car runs great now, no problems! heres a tip for you, he told me if you ever need to replace electrical parts, dont go through an auto parts store, just get them through the dealer so you know they r exact and a quality product. this wasnt the first time i had a faulty product from an auto parts store either, so im sticking with his advice. But good luck to you! This was a couple years ago, and i cant remember exactly what relay it was, but i was above the ECM from what i can remember, and i think it was for the fuel injection wiring harness if i remember right from looking at the schematics.

 

[jrichker]

Dump the codes and see what the computer says is wrong…Codes may be present in the computer even if the Check Engine light isn’t on.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

See http://www.troublecodes.net/Ford/

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see http://www.midwayautosupply.com/pc-7208-90-equus-digital-ford-code-reader-3145.aspx – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30.

 

[Gunnerm1]

"F'n relay that i had already replaced! THe one that i replaced it with was faulty, a brand new one, go figure! s"

Funny you just said that. I Just finished up my engine build, and the car would not start. The starter I had on it crapped out after several attempts at cranking the car. I took my old starter to the auto parts store and had them test it. It failed their bench test. They had two starters in stock so the clerk goes back and gets one and rings me up. For some reason the little voice in my head said----- have them test the new starter----. I ask the guy to test the new starter and he gives me the typical sideways glance like he has much better things to be doing, and that I am wasting his time.
Anyway he puts the "brand new" starter on the bench test and guess what? It fails, it does not even try to turn over.
So now the guy is not so smug, goes to the back , gets another and test it. Bingo, i have a starter that works now. I was sure to get the life time warranty.
If i had not known any better I would put the starter back on the car, and thought that it was some other faulty part of the ignition. so to make a short story long. I agree, buy ford parts or at least have them tested and keep your receipt.
P.S. the timing was off one tooth and thats why it would not start...fixed now.

i had the same problem with my 90 Notchback. THe car ran fine at lower rpm, cold, hot, raining, whatever. BUt i would rev up to over 3500rpm, and it would just break up and carry on. I checked everything possible, MAF, TPS, coil, plugs, wires , Air idle sensor, and so on. wasnt any of them. i asked my dads one friend who owns and operates a mechanic shop and he said it sounded like a relay problem. So i just started replacing the relays for the fuel injection and a bunch of other ones. THere are a couple relays down in the passengers side kick panel above the ECM. I replaced those and still had nothing! same F'n problem! So i crumbled and took it to my buddys friend who is a master tech at a Ford dealership and specializes in electrical work. He went over the whole wiring harness in the car and it came down to the F'n relay that i had already replaced! THe one that i replaced it with was faulty, a brand new one, go figure! so he put in a MOTORCRAFT replacement and the car runs great now, no problems! heres a tip for you, he told me if you ever need to replace electrical parts, dont go through an auto parts store, just get them through the dealer so you know they r exact and a quality product. this wasnt the first time i had a faulty product from an auto parts store either, so im sticking with his advice. But good luck to you! This was a couple years ago, and i cant remember exactly what relay it was, but i was above the ECM from what i can remember, and i think it was for the fuel injection wiring harness if i remember right from looking at the schematics.

 

[Bottomlesspit]

Axlenut,
I had the same problem years ago on my 93 vert. I spent countless hours and money chasing it. My problem turned out to be the TFI module on the distribitor. IT worked great until I would go above 3000 rpm and then it would start cutting out.
I followed a similar path to what the other guys have been saying. I bought the Auto Zone special TFI and continued to have the problem. I finally bought a FORD TFI and it solved the problem.
Just something more for you to check. Good luck,
Ken

 

[warlockpain]

how long has it been since the fuel filter was replaced? had a similar problem on my 91 coupe and the filter was the culprit. if it's been a while you may want to try replacing it. even if it doesn't solve your problem,it's good maintenance,easy to replace,and cheap.
just a thought!

 

[axelnut1]

Not cutting out ,but flooding

I got behind the mustang in my truck today and it is blowing black smoke at wot. It is flooding out. Anybody have any ideas???

 

[warlockpain]

possibly ruptured diaphram in the fuel pessure regulator?

 

[hogt2]

I had a similar problem with car missing(cutting out) under load around 3500 and up. Turned out to be the coil took a crap. Buy a cheapy one to trouble shoot with. If that solves your problem buy a good one(msd). let us know.

 

[axelnut1]

Fuel pressure

If the diaphram was ruptured, wouldn't it affect the car in all rpm ranges?

As for the coil, I have a MSD on it now.

Does anybody think the MAP could be causing this?

 

[greg251]

Bad ignition module will do what you describe.

 

[Bottomlesspit]

Yep, see my post above. Just like greg said!
Ken