What are the most common causes for this code?

 

What car has the code?

 

1996 XJ6. Exhaust Has a fluttering sound on the driver's side at an idle & when you put the car in gear, it gets worse. Touching the gas peddle at all causes the motor to stall out & die before the car even moves. Car has new Catalytic Converters, Plugs & Coils

 

Also seems to be backfiring through the throttle body if gas pedal is depressed while the vehicle is in park.

 

P1775 indicates a possible transmission problem, JTIS 21 says read transmission codes, which a generic reader can not do.

I wonder if that is the correct code. Could the reader be in error? Even if the coils are new, there could be a problem with them. Lots of info here on coils if you use search. Also, are the plugs the recommended Champions?

 

P1775 will be set by an engine stall so it is an effect of the problem you have not the cause of it.

 

If that's the case, I wonder if the throttle body throat and butterfly may be gummed up.

 

My guess is #5 and #6 coils are reversed.

Just a guess?

bob gauff

 

I cleaned the throttle body about a month before this code popped up, replaced the coils & replaced plugs with the recommended plugs. I had driven the car about 40 miles that day, parked it & about 3 hours later, got into it & it seemed to be in what I guess is limp mode & stalled out a few times. It took a long time before the car would start again. ( about 45 minutes each time ) The last time it started, I was able to feather the gas legal to get the car back up to the posted speed limit to get it home & I parked it. Now it starts right up, but has that flutter in the exhaust & the other issues I named above. Other than the flutter, it seems to idle fine, but starts backfiring through the throttle body & any time you attempt to apply very much throttle.

 

'Backfiring' through the inlet manifold is usually an indication of a very lean mixture.

Has the fuel filter been renewed? Have you checked the fuel pump pressure?

 

The fuel filter has been replaced. It is about 2 months old. I have not yet checked the fuel pressure. I'll check that & get back to you tomorrow.

 

Fuel pressure is good. I took a short video of what it is doing, but I don't have a way to convert it so I can post it on here. Do you have an e-mail I could send it to?