I just put a new block in my 87 gt hatchback. Timing is at 10 degrees, new O2 sensor, new plugs, wires, ignition, and distributor. Car is still not tuned right. Boggs when ever I hit the gas more than half way. Still running rich. back fires after about 3 grand. Any suggestions?

8/24/2006 3:28:31 PM

are you sure timing is at ten. did you put the dizzy in 180 degrees backwards

8/24/2006 4:16:03 PM

yah went from a civic to a stang good choice

8/24/2006 4:37:42 PM

i vote something timing related. What pulleys are you using? aftermarket? the ones that came with the car?

8/24/2006 4:39:49 PM

Did you pull your pill before you set the timing?

I bet timing as well. It's way too retarded.

If you don't pull the pill (the little inline dongle that plugs into the wiring harness) the computer will advance no-load timing at idle an assload. You go to set it with the light and you end up retarding the fuck out of the timing, giving you the symptoms you described.

8/24/2006 5:08:06 PM

i dunno about ignition timing, but are you positive the timing chain isnt off one notch?

8/24/2006 5:51:22 PM

^That's a very good point.

8/24/2006 5:53:36 PM

i had an adjustable cam sprocket one time one a 302 that i put in the wrong notch, thought i was advancing it 3 degrees and actually retarded it, and it did damn near the same thing, so a tooth off would make it real bad

8/24/2006 6:03:28 PM

yes I did all that and its still doing the same thing. If someone wants to take a crack at it and gets it working ill pay you a reasonable price

8/24/2006 6:32:40 PM

check the voltage on the maf, should be less than .70V between terminal D (top) and ground with ignition on, .20-1.50V at idle,

on the tps sensor, connect the positive probe to the dark green wire, and the negative probe to the black wire, with the ignition on, at idle should be .39V, WOT 4.84V

cheack for a vacuum leak, double and triple check your plug wires, firing order, and that #1 is on the right post, line it up tdc on the compression stroke and pull the cap and check, the work your way all the way around the engine (13726548) counterclockwise looking at it from the top, and remember ford is:

4 8
3 7
2 6
1 5
front

static timing should be 10 degrees with a maximun computer advance of 17-23 degrees
unplug the single wire connector and take the vacuum hose of the distributor and plug it when you set it, then when you hook it all back up, check to make sure the module is advancing it.

other than that, i have no freakin clue without getting deeper into, a lot more than you can do with an ohm meter, like checking the cps and shit

8/24/2006 9:08:33 PM

I dont think the rich problem has anything to do with your bogging problem. My first advice would be to clean your MAF sensor, and check voltages, then also check and or clean the Incoming air temp sensor located between the MAF and TB, then the IAC motor, and the TPS, which are located on the TB on the 94-95 5.0s, but im not sure about the fox setup. Then check your spout connector, if its out the car will run like shit, which might be your problem, or maybe the spout connector is bad, which is a semi-common problem on 5.0s, and if all that fails do like 69 said and bring the motor to TDC to see if that helps anything. let us know

8/27/2006 4:15:02 PM

in the 240sx world, those symptoms are classic unclean/nonworking MAFS ones

8/27/2006 4:19:55 PM

I wish it was just a simple MAF sensor but on an 87 mustang GT they are speed density so they dont have a maf sensor. I will check the IAC and the TPS. Thanks for all the informations guys. Some has helped so far. Its not running rich anymore I found the vacuum leak. The person who put my new block in did not put a intake maifold gasket on. But it is still bogging out. Feels like its not getting enough air or fuel mixture. I will try the IAC and TPS. Everybodys information has been helpful.

Thanks

8/27/2006 6:14:19 PM

TPS should be around .95V at idle and at least 4.5V at WOT.

Do you have fresh gas in it?

8/28/2006 8:12:21 AM

^.39 and 4.84 actually

8/28/2006 11:50:48 AM

ahhh the 86-87 speed density cars, I know nothing about how those work.

8/28/2006 4:58:42 PM

Quote :

"I will try the IAC and TPS. Everybodys information has been helpful. "

I would forget about the IAC if your idle holds stead and doesn't surge or stall.

The TPS? Yeah, check that to make sure you have a clean, uninterrupted sweep from idle stop to WOT with no dead spots or spikes. 69 gave you some good values to look at.

Have you pulled any error codes? You need a Mityvac or equivalent to check the MAP sensor, but that may need doing as well.

8/28/2006 5:39:18 PM

.95 closed throttle. Where did you get .39 from?

8/28/2006 6:04:37 PM

Actually, .95 sounds much better.

8/28/2006 6:27:20 PM

^^ factory spec

8/28/2006 8:48:42 PM

Everything I've ever seen on Ford EFI says .9V or so at closed throttle, and the mustang boys swear by .99V.

[Edited on August 28, 2006 at 9:30 PM. Reason : .]

8/28/2006 9:30:07 PM