Car is missing bad..

[Na5.0HO]

OK guys, I had a small miss start to occure and then my intake cracked.

Replaced the intake with a PI and adaptor plates and the miss is still there.

I've posted multiple times and haven't found the answer yet.

It misses at random at idle, and constantly in drive. Also, if I load the tuner it seems to miss more both at idle and in drive.

I had the tuner programmed for the intake to provide more fuel.

I've gone over and regapped, sealed all the plugs and wires. Plugs have about 100 miles and look very white.

Does this sound like my fuel pump is going bad??

I'm stumped

Thanx, Jason

 

[Kilgore Trout]

Fuel filter?

 

[DBMSTNG]

something fuel related. maybe injectors or pump.

 

[Na5.0HO]

Forgot to mention... fuel filter has 100 miles

So, you guys would say fuel over something like a bad coil pack??

Car only has 51k miles..

Thanx

 

[DBMSTNG]

Forgot to mention... fuel filter has 100 miles

So, you guys would say fuel over something like a bad coil pack??

Car only has 51k miles..

Thanx

the plugs wouldn't be white from a bad coil pack, they'd be black. the white means you are running lean. plus it is very unlikely that all the COP's would go bad at the same time.

 

[Na5.0HO]

Thanx for the input, and on a side note... my car has 2 coil paks instead of COP like yours. (I know, it's not fair for us pre - 99 guys.

 

[DBMSTNG]

sorry, didn't notice it was a 97. but anyway. maybe try to clean the injectors or swap a fuel pump. they are cheap for your car.

 

[Na5.0HO]

Looks like I'm trying a new fuel pump... we'll see after that.

 

[white96blown2v]

despite the clean plugs , there is still the possibility of a coil pack going bad. Also have you checked for vacuum leaks as this would cause a lean condition as well.

 

[Na5.0HO]

despite the clean plugs , there is still the possibility of a coil pack going bad. Also have you checked for vacuum leaks as this would cause a lean condition as well.

Is there any easy way to check for a vaccum leak?

Thanx

 

[MaxedGT]

You can use a can of throttle body cleaner and spray around the engine. spray everywhere at first, while the engine is idling. If there's a leak your idle will change when the cleaner is sucked in and burned. But if coolant got into your spark plug holes, and caused a missfire, the wire and ouside of the plug could be carbon tracked and no amount of cleaning will fix that. If your wire ends don't look brand new, inside the boot, replace them. Check the outside of the plugs for carbon tracking on the insulator as well. Another thing you can try is to use a spray bottle of soapy water and spray it on the wires and coils while the engine is idling. If the engine misses when you spray a wire, or you see or hear a spark jump, you found your problem.

 

[Mike97gt]

well i would check the ignition first.. 99 percent of misfire problems are igntion related..

 

[Na5.0HO]

Thanx for the help guys, alot of coolant got everywhere when my intake blew. (Lost all my coolant in 1/2 a mile!)

MaxedGT, could you elaborate a little on what "Carbon tracking" looks like?

Thanx

 

[nyuk98gt]

Na5.0HO:

Plug wires may look fine externally or they may show some spiderwebbing outside. Start you car in the garage, lights off, garage door down, and open the hood and look for arcing. If the insulation on a wire is bad, you will see it arc. Coolant can kill plug wires, too.

Did you know that the plug boot slides on the wire? So, it is quite possible (I did this!) to have the boot seated in the hole but the plug wire metal connector not connected fully on the spark plug tip. You have to gently pull or push the wire (whatever is needed) at the point where it enters the boot until the wire is long enough to ensure that the metal connector is completely snapped onto the plug when the boot is in place (the little rubber flange is flush with the top of the hole.

Use a dab of dielectric grease to lube the inside of the boot and metal connector. This will seal moisture out of the boot and ensure good conductivity between the connector and the top of the plug.

The Haynes manual ($20 at AutoZone or Borders or ....) has a procedure for checking coil packs and the wire harness feeding the coil packs.

You can also check the resistance of the plug wires. Measure the length of the wire and the resistance and then calculate the ohms per inch. All wires should be pretty much the same. If you find a wire with very high resistance, then you know that it is probably bad or going bad.

HTH,

Chris

 

[Na5.0HO]

Thanks alot Chris. I have lots of things to test out now.

Also, you have my ideal setup (plus a shortblock & blower) Any times outta those mods?

Thanx,
Jason

 

[MaxedGT]

Thanx for the help guys, alot of coolant got everywhere when my intake blew. (Lost all my coolant in 1/2 a mile!)

MaxedGT, could you elaborate a little on what "Carbon tracking" looks like?

Thanx

Carbon tracking looks almost like pencil lines. Usually jagged lines. And I agree with the previous post, that your miss is likely ignition related.

 

[nyuk98gt]

Na5.0HO:

No track times for this old fart. I just go to watch the mayhem!

Get busy now and post back what you find, please.

Chris

 

[Na5.0HO]

Ok.. spent a couple hours missing around with the thing..

Spark plugs seem OK. They all look good, snap on tight, and pass the lights off test.

New stuff is when I give the car throttle, it stumbles if I try and hold it constant, lags a bit, and RPM's want to drop way down after I let off (2g - idle)

Also, there is an intermittent ticking sound from near the TB passenger side.

When I checked the plugs, the passenger side were slightly discolored and the driver side were still pretty white.

What do you guys think?
Thanks alot,
Jason

 

[Mike97gt]

i still think it's ignition related.. can you isolate the cylinder miss firing

 

[Na5.0HO]

i still think it's ignition related.. can you isolate the cylinder miss firing

I haven't been able to identify it so far.

I've now established that my fuel system is fine and I don't have a vaccum leak so it must be electrical / ignition related.

The ticking is still there on the passenger side near the TPS and the last spark plug wire on the passenger side keeps blowing off. Unfortunately, the two don't seem related.

Does anyone know what could possibly cause a miss and would make a loud tick every time??

Thanks,
Jason