1992 XJ40 sitting 13 years won't start

Hello, new to this forum, just bought a 1992 XJ40 Majestic that has been sitting for 13 years. So far had fuel tank cleaned and lined ,new fuel pump, new fuel filter, new injectors, new plugs, new crankshaft position sensor, new battery, new intake air temp sensor. Won’t start, gets right up to the edge of starting but won’t kick over. will run for a second on starter fluid. Any suggestions would be appreciated. Thanks Jay111

Welcome to the forum Jay. You didn’t mention the cap and rotor.

Joe77 Thanks for the welcome. The cap and rotor are good and it’s getting good spark.

Welcome to the forum Jay.
Running for a second ostarter fluid indicates a problem with the fuel supply. Can you rig up a gauge to check what the pressure is? Should be in the region of 38psi
The other possibility is the FPR, (fuel pressure regulator) positioned on the forward end of the fuel rail. If that fails open then there will be no pressure at the injectors.

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didn’t check fuel pressure but fuel pressure regulator is new.

I would be inclined to remove the injector rail and isolate the coil, with a large piece of cardboard over the engine just give it a crank and see that the injectors are actually firing fuel out in a good pattern.

Welcome Jay,

  1. Is the fuel pump working ? 2. have you replaced the Coolant temp, sensor?

Cheers,
Bruce

Fuel pump is new and working. Haven’t replaced the coolant sensor,will that keep it from starting? Can it be tested?
Thanks,
Jay

A couple of relays affect pump operation - definitely fuel pump relay and on some models oxygen sensor heater relay.
If either of these aren’t switching the pump won’t run.

Coolant sensor lets the system know if it’s a cold or hot start. Think of it like the “choke”. If its failed the cold start enrichment won’t happen, so sort of like “no choke” in old school terms. These things are reasonably priced, BTW.

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It has very good fuel pressure at the rail. It almost seems like the injectors aren’t opening but I tested with a noid and it was flashing. It gets so close to starting like it really wants to start but just won’t finally fire up. Changing the timing seems to have little to no effect on it.

But was it also clicking? Just because it receives power does not mean the are opening.

Hi Jay,
Yes if the CTS is faulty, or the wiring to the CTS is faulty you will have a no start situation.
disconnect the lead from the CTS turn on the ignition and you should have around from memory around 3.8 volts on your multimeter. ( I am not an expert on the XJ40 and the voltage figs are for the XJS but I am sure the principal is the same ) if ok then replace CTS
Good luck,
Bruce

Jay - you can test the CTS to see if the resistance is within spec:

Remove the connector and connect the leads of your ohm meter to the blades on top of the sensor. The resistance should be close to the table value according to the ambient temp.

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