Hi, folks! New to the forum, details about me in the "Greetings from Acworth" thread in the new members area.

Car in question is a US Market `93 with the 4.0ltr. six. Car takes repeated tries to get started, regardless of operating temp. Once started, runs fine with no missing, or hesitation (instant throttle response). So far, I've replaced the sparkplugs, the cap & rotor (reproduction parts, but Italian, not Chinese made), and fuel filter. I don't have the tool to meaure fuel pressure, so I've not done that. Any ideas?

Jay Roberts, Atlanta.
1993 XJ40 4.0

 

You didnt mention if you replaced the plug wires,if not when running open hood and look to see if any are arcing (if so replace them).Also check to make sure the coil is grounded well(no dirt or oilnear the unit).

 

Hi Jay,

and welcome to the forum.

Is it hot down there in Atlanta, Georgia?

This car has not been sitting around for a while has it? You do have GOOD gas in the tank, right?

For the simple stuff, follow what Haynes suggests in my thread, Roadside repairs.

If you do not have a Haynes, you should purchase one. Google for it and you may even find one on eBay.



Do you have an auto transmission? If so, do you have the same starting problem in "P" or "N"?

This may be a fuel delivery/injector problem. Squirt a little bit of carb cleaner or starting fluid in your air box and then try to start the engine.

You may find it starts right up.

Keep us informed.

 

Just try this :
Turn the key to II and back to 0 you should hear a noise , repeat it a few times and once you're done it , turn the key II and get it started , if it starts easily then you've a fuel pressure problem .
You should do this when your engine is hot

 

If you want to save some time and money I can get you a copy of the Haynes Manual...PM me.

 

Thanks for the replies, everyone! Sorry it took me so long to get back to you. Lumppy, I don't think it's wires, since it runs so well after it finally starts. I'll pick a dark night and go take a look just to make sure, though. TF, car *has* been largely sitting over the past few years, but we've run the old stuff out (and run a couple of bottles of injector cleaner through a couple of tanks). jrwb, thanks for the offer! The manual I have is the official Jag "Owners Edition" (the one with the red cover). Is the Haynes better? The Haynes I had for my older BMWs were pretty good, but the one I bought for her old Olds Bravada is terrible (I think they try to cover too many models in the regular-sized volume).

Regent, I'm seriously interested in your suggestion, since I'm suspecting fuel pressure anyway..I just want to make sure I understand. Are you suggesting turning the ignition on, and listening to the fuel pump run? And then turning the pump on & off several times (through use of the different positions on the ign. switch) to try to get the pressure higher before engaging the starter? Just want to make sure I'm doing it right.

And yes, it's HOT in Gawgia! My SCCA division held a hillclimb south of Deal's Gap last weekend, I went to go flag it-thinking that it would be a nice break from the heat. They were having a heat wave as well..

 

Hey friedgreencorrado (lovely name )
When your car is hot (not the engine is cold ) cycle the key a few times 0 to II , you will hear a fuel pump noise . Then, start your engine , if it starts w/o any difficulty you have got a fuel pressure problem .
My old 88 was doing the same , I had to crank it a few times to get it to start then a Jag mechanic advised me this way , worked fine for me

 

I don't know how the Haynes compares with others, but it seems good to me - has most of the info I require...

 

Okay, tried Regent's test. It started much easier after that (2nd try instead of 5th or 6th). The pump sounds like it's straining a bit as well. I'm still thinking fuel pressure. So, should I suspect what I'm told is the "sock filter" on the tank pump? I've heard the pump can ingest it if the car has been sitting for awhile. Am I missing something simpler here?

Car still runs beautifully after you finally get it started!

 

When cold, before you even put the ignition key in the switch, do you have good pressure on the fuel rail? It should be somewhere around 21 psi if you have a guage. I've run into similiar problems on some U.S. autos and the fuel pressure regulator is letting the pressure bleed back through the return line. When you are starting it, the pump has to build the pressure back up. The pressure regulator acts as a check valve to hold pressure on the rail for starting. Luckily, the regulator is on the fuel rail, not built into the pump in the tank like my Jeeps. Hope this helps.

Thanks RegentV12, I had my wife start doing this in her Jeep, (cycle ignition switch on and off several times before starting) helps to save battery instead of cranking. Her fuel pump and regulator is 200.00, so she wants to get as much life out of it as she can before we drop the tank and replace it.

 

you're getting some good advice on the fuel regulator and the fuel pump. I have had both problems on my jags. You really need to have a fuel gage to help with an accurate diagnosis. Norm

 

I guess, 21 psi can be considered fuel system hold pressure, but

Fuel pressure:

Ignition ON, engine not running .................... 38 to 44 psi

is required for an XJ40.

 

Eh, I was afraid of that. I don't have one. <grin> I was looking at buying a cheap one, but most of those seem to only have the fitting to test one particular system. Saw a great one with 30something interchangeable fittings from Mityvac..but it's $250. Can anyone tell me which port fitting I need to check the Jag? Perhaps I can borrow one somewhere.

In related news, I showed her Regent's trick to "pressure up" the system..and she's driving it again. I figure that driving it is good (especially if I put some more "injector cleaner" in it). Either it'll fix itself, or the fuel pump will die from the strain, and I'll finally know what's wrong with it..normally, I wouldn't do this, but she's a tough girl. Detention Officer (PC title for "jail guard") for the county jail, she can take care of herself long enough for me to get there if it dies on the road. Thanks again for the advice, everyone..I certainly appreciate it!