95 mustang check engine light came on bucking in 2nd gear code 51 / 511.

hottwheels04 · Sep 15, 2013

95 mustang check engine light came on bucking in 2nd gear code 51 / 511.

Like title states My check engine light randomly came on, and I notiched the car is bucking accelerating not smooth in 1st and 2nd gear kind of lag then it goes and kind of bucks. I went to autozone to check with obd1 scanner what a paint, the number I belive Im getting is 51 or 511, which is saying something to do with the ecm computer and other is for temp sensor or t start etc. Not sure that would cause that problem. But I know last year or year before I think i had check engine light as well code 511 and it was nothing you reset it? Cant remember. I know the t stat and temp sensors are new. And a new coil just replaced just about everything I was thinking it was bad gas or bad 02 sensor or a bad coil pack. what code it be?

2 codes I got?

51

Engine Coolant Temperature (ECT) sensor signal is/was too high – ECT

and

511

(O)

No power to PCM pin 1 or bad PCM (processor)

teal95gt · Sep 15, 2013

does it idle really rough and die sometimes?

hottwheels04 · Sep 15, 2013

teal95gt said:
does it idle really rough and die sometimes?

eh yes and no, but I notice it bucking more in low rpms in 1st and 2nd gear and you full throttle it kinda hesitates then goes and kind of bucks its not smooth. I just read code 51 is to do with engine temp sensor it can be making it run @ wrong temp or make the computer make it run rich? which makes sense, but had this problem fixed and I have new sensors sucks! not again! lol

teal95gt · Sep 15, 2013

I had a similar problem on mine recently before I took it in for a tranny rebuild and some other shit. My car would start some days and some other days not turn over unless I had my foot on the gas, I had to two foot it a lot because if I slowed down it died at lights haha ended up being a bad IAC and some other sensor I forgot the name of it lol, if you have any good mustang places near you bring it there and I'm sure they would let you troubleshoot it there and change new parts in and out.

hottwheels04 · Sep 15, 2013

teal95gt said:
I had a similar problem on mine recently before I took it in for a tranny rebuild and some other shit. My car would start some days and some other days not turn over unless I had my foot on the gas, I had to two foot it a lot because if I slowed down it died at lights haha ended up being a bad IAC and some other sensor I forgot the name of it lol, if you have any good mustang places near you bring it there and I'm sure they would let you troubleshoot it there and change new parts in and out.

Yeah Im thinking it is the bad temp sensor, I got a local guy who works on stangs Im going to ask him if he thinks its that, I have mustangs unlimited local in my state Im going to bring back the temp sensor and tell them this new 1 is still no good and try a 2nd 1 and see if thats what it is, and see what my guy can tell me what it could be

Ferocious · Sep 15, 2013

My car use to have code P0117 (Engine Coolant Temperature (ECT) Circuit Low Input) which I found to be a case of exposed wires right by the pigtail to the coolant sensor.
A new pigtail and sensor fixed that issue. Not sure if yours is the same, but it's worth looking at your sensor.

CC'S95GT · Sep 15, 2013

Where were you reading the codes from? under the dash? under the hood?
94/95's GT's (OBD1) have a 3 digit code.
96 and up (OBD2) have a 4 digit code.

Twista · Sep 15, 2013

95 has three digit trouble codes. .. and 118 would be signal to high on these cars.. not 51.

I think your reading the flashes wrong.

hottwheels04 · Sep 15, 2013

Twista said:
95 has three digit trouble codes. .. and 118 would be signal to high on these cars.. not 51.

I think your reading the flashes wrong.

No right here is from the Haynes manual for obd1 94-95 mustangs

2 codes I got?

51

Engine Coolant Temperature (ECT) sensor signal is/was too high – ECT

and

511

(O)

No power to PCM pin 1 or bad PCM (processor)

hottwheels04 · Sep 15, 2013

CC'S95GT said:
Where were you reading the codes from? under the dash? under the hood?
94/95's GT's (OBD1) have a 3 digit code.
96 and up (OBD2) have a 4 digit code.

yeah its a 95 so its obd1 can only read it under the hood on the passenger side firewall theres the diagnostic plug in on the wireing harness in the engine bay only way we can, only 96+ obd2 can you read with the plug in scanner under your dash in your car, or a v6 cars

CC'S95GT · Sep 15, 2013

Just making sure.
We've had people try to read OBD1 codes from OBD2 port then can't understand why nothing or crazy codes come up.

hottwheels04 · Sep 16, 2013

CC'S95GT said:
Just making sure.
We've had people try to read OBD1 codes from OBD2 port then can't understand why nothing or crazy codes come up.

I hear you!

CC'S95GT · Sep 16, 2013

Let's start with the basics, how long has it been since it was tuned up? including fuel filter?
Have you cleaned the MAF and inlet temp sensor?
How old are the cat's? clogged possibly?
The MAF could be bad also. That can be tested by unplugging the MAF while the car is running and listen for any change in the idle.

hottwheels04 · Sep 16, 2013

CC'S95GT said:
Let's start with the basics, how long has it been since it was tuned up? including fuel filter?
Have you cleaned the MAF and inlet temp sensor?
How old are the cat's? clogged possibly?
The MAF could be bad also. That can be tested by unplugging the MAF while the car is running and listen for any change in the idle.

I just put a new fuel filter new mid pipe headers, 02 sensors, temp sensors, spark plugs and engine rebuild back in june. I did unplug the temp sensor and maf and unplugged the battery and it seems to idle and run fine now. and since I reset the battery the check engine light went off drove it for 10 miles it didnt come back on knock on wood! so hope it was random glitch needed to reset.