History

Removed unused (never used so not an issue) nitrous kit and all associated stuff.
My car was running good for a while and then my alternator took a **** along with the battery.

I replaced the alternator and battery and the car ran fine for a few weeks.

I was just cruising around taking my daughter to school and this last saturday when I pulled out it was stuttering at almost any speed. When WOT it would stutter as well.

I had what I thought was bad gas in the car so I put some stuff from another station to try and dilute any water (silly thought in hind sight since water doesnt really do good in gas)... and it didn't help.

Troubleshooting:

I have had them (alternator rebuild place) look the alternator, the bench test seemed fine but they replaced the voltage regulator anyway. I have tested the battery and it's good.

I replaced the fuel filter and cleaned the air filter.

I reloaded the tune (91 tune Doug made for my MAC longtubes and steeda intake).

Now the car runs decent but any attempts to get past 2900/3000 rpm it stutters to the point that it slows down and if I go WOT it slows down, almost like the engine has shut off and it using compression to slow down.

I no longer suspect bad gas or rather I suspect it less now.


HELP:

What can cause my car to stutter/fall on it's face at 3k? What happens at 3k or around there that would cause the problem?

I'm just theorizing at this point as I know little about the electronics.

I'm also getting an intermittent "check charging system" message which I can't for the life of me figure out whats wrong if the battery and generator are good.


Any help would be appreicated.

 

.. sorry edited soething out

 

Could it be a bad fuel pump?

Car seems to sutter at almost any speed/rpm now.

 

I had a very similar problem a 99 V6, turned out to be clogged cats. Do you have high flow cats along with your longtubes?

 

I'm catless (in california)


Someone I know up in Santa Barbara mentioned O2 sensors (the fronts) being bad... ??

I nail it to floor WOT and still have same issue (at WOT the O2's are bypassed, correct?)

Fuel pump at dealer is 278$....

 

Pull the plugs and see how the look. Do a compression test while you have the plugs out. Do some data logging and see what the fuel system is doing.

 

I thought I remember something about a faulty cam sensor TSB, but at the moment I can't find it. The cam sensor could cause that charging system messege to show up due to faulty input signals coming into the computer. Check your fuel pressure though too, it very well could be a bad fuel pump along with another faulty alternator.

 

Do you have a link to that tsb?

Thanks

And do tsb's require you to pay anything at dealer? How do I tell them this needs done if it is problem?

?

Thanks

 

I believe the cam timing changes around 3k rpm. Catalog that and see what its doing.

 

I meant to say datalog. Lack of sleep.....

 

I had an issue very similar to what you described on an older mustang that I had....and it turned out to be bad sparkplug wires...

I guess spark wasn't getting to all the plugs at high rpm...it would do ok at low rpm's but as soon as I tryed to speed up it would sputter.