I just got done doing head gaskets on this 2000 s-type 4.0. I pulled the engine and transmission out of the car together, and now that they're back in, I'm coming up with a few problems.

First, some engine codes:
P0301 Cylinder 1 misfire
P0430 CAT efficiency bank 2
P0193 FRP sensor circuit high ouput

Second, when I turn on the blower motor, I can hear a hissing sound. The only way to make it stop is turn the HVAC completely off. As an added bonus, the a/c doesn't blow cold at all. I know the compressor clutch is fine, I've watched it cycle on and off. I didn't open the system at all when I pulled the engine; all the a/c components stayed hooked up in the car.

The reason I re-did the head gaskets is because I suspected they were bad... the guy I got the car from ran regular unleaded fuel in it, overheated it at least once, and just generally ignored lots of problems with the car. The cross-over water tube in the front of the engine had melted a nice hole in it and spilled out all the coolant the last time it overheated. The coolant looked disgusting when I got into it; the water pump was semi-clogged with a grey sludge, and so was a diverter valve up at the front passenger side of the engine bay (dual climate control valve?). The radiator was no better.

Just looking for some insight on where to start with this thing. I've been at it more times than I care to admit to, and am getting sick of it.

 

Did you surface the heads? It's an all Aluminum motor and if it over heats it will warp.
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No, the heads weren't resurfaced. I wanted to, but the guy paying me to do this work didn't want to spend the extra money on it.

It did run perfectly right after I put it together though... I had all 8 new spark plugs in it and it ran great. Two days later though, it started with the misfire. The hiss from the HVAC has always been present since I put it back together though. Did I miss something in the re-assembly? Or put something in the wrong spot?

 

Misfires are rarely plugs on S-Types. Usually coils. Sometimes wiring.

 

I can replace a coil no problem. I've had those stupid valve cover plates off numerous times now. Which side on the Jag is #1? Passenger side?

And what about the hissing noise with the HVAC?

 

You need to download the 'ENGINE COURSE 168' in the large file download section.
It is a student guide that I uploaded years ago.

For the AJ28 engine, #1 is the right front cylinder. Ford/Lincoln 3.9 liter coils are the same.

You can swap coils with another cylinder to see if the fault follows the coil but they are fairly inexpensive to replace.

Hissing A/C system is sometimes an 'undercharge' fault. I would evacuate the system and weigh the refrigerant to verify the correct charge.

bob gauff

 

So that's front right while looking at it from the radiator? Or front right from the firewall?

 

All directions on a car are standardised as if standing behind it looking forward. That's how RHD & LHD are decided.

Get the Vehicle Spec PDF from stickies as it has diagrams and far more.

 

Fixed it. Problems with the ignition coil. Go figure.