Detonation: I have some questions...

[95mustanggt]

OK, my car is still detonating. I battled this beast for awhile and after I changed my MAF everything seemed fine.

Now my car does detonate again. There are no codes and everything seems to be ok. It is not temp related, A/C makes no difference.

I was about to give up and just call my car "tempermental" when I noticed this one Correlation:

Some times I smell unburned gas, on those days the car runs like a bat out of hell (of course this is how I want it to run)

On days that I don't smell gas, the car detonates and seems to lack power (this is bad, car is slow and detonation is bad for my engine).

So my question is what's wrong? I haven't measured my fuel pressure (don't have a gauge....yet ).

Any insight would be welcome!

[Reipen]

just about summed it up for me, i have the same car, cept mine is a vert aode

i onl experience pinging, when i do experience it, in between 4 and 6k rmp in 3rd gear.

[jimberg]

If you have an off-road h-pipe, how could you possibly have a cat-back? ;D

I can't believe you are still having this problem.

Get yourself a fuel pressure gauge and do some leak down tests.

[95mustanggt]

Originally posted by jimberg
If you have an off-road h-pipe, how could you possibly have a cat-back? ;D

How's that?

[95mustanggt]

Originally posted by jimberg
I can't believe you are still having this problem.

Get yourself a fuel pressure gauge and do some leak down tests.

I can't believe I'm still having the problem too. I've done a lot to try and fix this.

The thing that confuses me is that the problem is interminant, which to me means electrical. The fuel pump is electric and so are the injectors. I guess I'll have to check them out.

Either that or replace them with a 190 lph or 255 lph pump and 30# injectors when I do my Heads/Cam/Intake I wonder what would happen if I told my wife that I needed TFS heads/intake and a good cam to match the fuel system I want to "fix".....

[jimberg]

I wonder what would happen if I told my wife that I needed TFS heads/intake and a good cam to match the fuel system I want to "fix".....

That's what I always tell my wife.

[11secondGT]

My wife has 1995 GT with a five speed and has pinged since we bought it with 40 thousand miles on it. What I have done to fight this is installed a 160 degree thrmostat never exceed 14 degrees base timing and run 94 octane fuel at all times. When I go to the track I keep the heater on in the staging lanes and keep the heat out of the car. I try to keep the needle on the temp guage around the n and o normal at the track. These computers suck and that is why so many people make the switch to the a9l computers that were in the 89 to 93 non cobra cars. If you are having trouble I would lower the base timing or run better fuel immediately to stop it. I think maybe the reason that your car dosn't ping when it smells rich is beacause the car is running in open loop mode such as start up when it is supposed to run rich. When it goes into closed loop at full operating temperature it reads off the sensors and starts adjusting timeing and fuel etc. wich leads to a ping. What I did to counteract this at the track is run a low thermostat and keep the car out of closed loop so it dosn't have a problem. The car will show as much as a 2 tenths difference and 1.5 mph difference between the two.

The car is this,

1995 Mustang GT
Mac cold air kit
cobra intake with 1.7 rockers
4.10 gears
full exhaust, headers, x pipe flows etc.
pulleys, bar cut out of meter

best et is 13.3 at 102.5 mph on street tires 2.03 60 foot

Either do this or swap computers! It is the only way!!1

[95mustanggt]

The 95's do seem to have a lot of computer problems. I do run a 160* thermostat (to match my ADS Chip). My temp gauge always stays at the very start of the "Normal" range (doesn't even touch the "N"). Base timing is at 9 degrees.

Would a custom burned chip help? Once I have done all the work to my car, I want to get a custom burned chip.

[PKRWUD]

you have already taken care of your plug wires, right?

Take care,
-Chris

[95mustanggt]

Originally posted by PKRWUD
you have already taken care of your plug wires, right?

Take care,
-Chris

Yes, I had 4 wire separators and I was only using 1 per side, so I added 2 to the drivers side and made sure no wires were touching. The passenger side is another story. When I get some more time (get the car back to Canada to my place with a garage) I'll re-run all the wires with all the proper clamps and holders.

I'm really starting to think it is a fuel problem. But without checkin the fuel pressure there is not way to tell for sure.