Did you check the fuel for water?

 

Yes and it was all fine.

Fortunately this evening she decided to play ball, reconnected the maf again with better connectors and she fired up 🎉

I think with all the trying and starting and stopping it had probably flooded and needed a bit of time.

So now she's running on sitting with a couple of small issues (I hope)

1. Oil guage isn't working
2. Temparture gauge isn't working
I imagine both of these are possibly to do with the sender units being gummed up after sitting for so long.
3. In drive and reverse she idles around 700ish rpm but if I go into park or neutral she jumps up to around 1500.

Haven't had a chance to do any research yet so if anyone could shed some light that would be great

 

High idle can be a few things. Could be a stuck/dirty idle air control valve. Be aware that the bolts are held in with loctite, if you try and remove them, they will shear off. Heat them first with a small torch to break the bond of the loctite, they need to be about 150C or so.

The throttle body could be gummed up and the throttle plate isn't returning to closed. Clean the throttle body and also try closing it by hand to see if it closes a bit further.

Throttle cables could be maladjusted and holding the throttle open slightly. You can disconnect them at the throttle body and see if it makes a difference.

Finally, the throttle position sensor could be bad/replaced and not calibrated. If the ECU does not see the proper voltage, then it thinks the throttle is not closed and will make no attempt to actuate the idle air valve to control the idle speed. To reset requires dealer level software.

 

It’s been awhile since I’ve read through this thread.

1. LHD5642AA - shouldn’t cost a lot and probably take you 20 minutes to replace. It’s on the engine block, drivers side, close to the firewall. I forget what sized deep socket you’ll need to remove/replace, but you’ll figure it out. Common failure, and common source of oil leak! I might recommend a thread sealer here.

2. LHE1600AA - if the first one took you 20 minutes, this one should take you 10 minutes. It’s on the thermostat housing. Should take you longer to find it! Just make absolutely sure you’re pulling the correct sensor and that the engine is cool. Not uncommon, as I’ve experienced one of these failures myself.

3. Clean your throttle body. Remove it and clean the whole damn thing. Inside and out. You’re gone be surprised how dirty and sticky it is. You’ll use an entire can of carb cleaner, so wear gloves too. You’ll need a 10mm socket to remove the four bolts and two golf tees to block off the small coolant hose that connect to the underside of the throttle body. You’ll want to remove the TPS to make sure it does get doused with carb cleaner. While off, you may want to slightly enlarged the two plastic holes on the TPS used to connect it to the throttle body.

Once cleaned, you can slacken the TPS screws just enough so you can adjust the position by hand force. You don’t want it loose, but not fully tightened. Reinstall the throttle body, making sure everything is connected. There’s no gasket between the throttle body and the engine, even though it looks like there should be. It is metal on metal.

Now start the engine and while it’s running at 1,500rpm or what ever, stick your hand and try to twist the TPS that you never tightened down. You should be able to adjust the rpms. Since the engine is still cold, you should be able to get it to the 700s, so that it can idle at about 580 when hot. If you want to do this (carefully) when the car has warmed up some, that’s ok too. I’ve done that. Wear long sleeves.

Once you’ve gotten the idle dialed in, tighten those bolts on the TPS down so they don’t move. You can wait for the car to cool down first, if you want.

You can also just skip the entire section, take it to a Jag dealer and let him reset the sensor for you, for $150.....but I’d absolutely clean the throttle body out first. That’s a step that shouldn’t be skipped, especially if you’re gonna pay someone to correct that sensor. Get that thing clean as a whistle, otherwise the idle setting will get lost as the gummed up butterfly plate loses its ability to open and close consistently.

This is a common issue with these engines.