I own a 97 xj6 vanden plas and it has been fighting to start and recently the check engine light finally came on and my obd port isnt working so i cant get a code but the car feels like its fighting for fuel maybe. I gotta pump the gas to help it start and when i idle it like burbles trying to stay on even when i push the gas it feel like it loses power or its delayed or something idk any suggestions? If you got any questions or responses on what it might be and how to tell please send them my way

 

With the possibility that the fuel pressure regulator may be bypassing too much pressure someone was able to pinch off the return line to modulate the pressure in the fuel rail . You can use vice grips . The return line exits the FPR to the bottom


My take on it would be to not fully clamp off the return line as this may put too much pressure in the fuel rail

Better to go from a loose clamp to a eventual tighter clamp try

Keep a watch on the voltage drop on starter sag does not get below 11.4 volts

You can swap the fuel pump relay ( # 5 ) with the ACC relay ( # 3 ) . This is if the relay power contacts inside are comprimised

Verify they have the same part #s

See page 19

On the OBD port someone had a bent pin in the socket that was popping the fuel pump control fuse

This is fuse # 10 ( red ) 5 amp of the right heelboard fuse box



Don't touch the large BT4 connector above the fuel tank yet until you understand the pain it is . But it's connection at pin 31 could be limiting the current flow from the control fuse # 10 to be able to properly close the power contacts in the fuel pump relay

 

The Crankshaft Position Sensor on the front of the engine might be bad. It "reads" the toothed wheel on the pulley. Check for 200 rpm on the tach while you are cranking the engine. If no rpms show, it is bad. If rpms show, it still might be bad. That CKPS is a part that should be replaced as preventive maintenance. One 8mm bolt, one wire connector nearby, easy.

 

Vee hav vaaayzz of making you resolve

The crankshaft position sensor is a inductor that will read 1300 ohms resistance as a basic reading

The fault code is PO335 , but this does not always show

The functional signal is a modified sine wave with a interruption as the missing tooth comes around

This single signal is used in a couple of areas of the ECU including the spark timing , fuel pump continuation " on ":after start sequence , as well as your Tachometer

Any one of these areas may not see a degraded crankshaft signal without giving a code , The last area from my understanding to fail is the Tachometer

The sensor can fail after it warms up and expands , debris on the face of the sensor , dirty connector , a bad splice in the wire loom as it goes over the fuel rail , corrosion on the ECU connector , and even a case where someone had a extra second missing tooth on the ring gear confusing the ECU

How the crankshaft sensor is used in the starting sequence as it relates to fuel pump commanded " on " is this :

As you rotate the key to run position before the start position the ECU provides a ground for 4 seconds to the # 1 fuel pump relay control half in order to charge or prime the fuel rail . This fuel charge is trapped by a check valve on the fuel pump itself and the fuel pressure regulator

In key start position ........

I'm losing my stuff so after lunch

Editing

 

Hi mh.anthony6,

Welcome to the Jaguar Forums! It's great to have you with us.

I edited the title of your thread to add the general nature of your inquiry so members who may have dealt with similar symptoms will be more likely to read and respond. Many of our knowledgeable members are very busy and may not take the time to read a thread with a non-descript title like "Please Help," despite the urgency implied by your creative spelling.

My first question is: Could it be possible that you got some gasoline that was contaminated with water? Did these symptoms occur suddenly within a day or two of purchasing fuel?

My second question is: How long since you gave your Jaguar a good tuneup (spark plugs, air & fuel filters, cleaned the major electrical connectors and ground points in the engine bay and trunk, replaced the engine coolant thermostat and tested the Engine Coolant Temperature Sensor (ECTS), ran a bottle of fuel injector cleaner in a tank of gas, load & conductance tested the battery, etc.)? Sometimes symptoms like yours are the result of multiple components misbehaving.

Parker's comments about the Fuel Pressure Regulator (FPR) are good; if the FPR does not hold sufficient pressure in the fuel rail, insufficient fuel may be delivered to the combustion chambers, or fuel that is not sufficiently atomized. An easy test you can conduct is to carefully pull the vacuum hose off of the FPR, turn the key to position II to allow the fuel pump to run its priming burst, then turn the key off and check the vacuum port on the FPR for signs of wet fuel, which indicates failure of the FPR diaphragm. This also allows unmetered raw fuel to be inhaled into the intake manifold, leading to rich running.

At startup, the Engine Control Module (ECM) first references the Camshaft Position Sensor (CMP) to determine Cylinder 1 Top Dead Center (TDC) on the compression stroke within less than one revolution of the engine. After the engine starts, the CMP is ignored and the ECM references the Crankshaft Position Sensor (CKPS) that Parker described to determine ignition timing. If there is a problem with the CMP signal, the ECM will revert to the CKPS, but it has to determine Cylinder 1 TDC by trial and error, which can take up to 30 seconds or more. So one possible contributor to your long crank times is a problem with the CMP or its electrical connection.

Check for cracks or leaks in the air intake plumbing between the Mass Air Flow Sensor (MAFS) and the Throttle Body (TB), or in the vacuum hoses and crankcase breather system hoses.

Regarding your OBDII Data Link Connector (DLC), check Fuse #6 (5A) in the trunk fuse box, and Fuse #10 (5A) in the right hand heelboard fuse box (front edge of rear seat, right side).

Cheers,

Don

 

I laugh every time I see this GIF. Thanks Parker, good to have you and your personality here again. A whimsical tech wit.

 

So ive replaced to fuel filter and the crankshaft position sensor. Still the same problem, but @don i have not done a thorough service of the car yet i definitely am going to now as i am just seeing your comment. I Appreciate the help and advice i am getting i will be in touch with what it was. Is there any way i can get a code without the port ? On my old Chrysler there was a way to get codes on the odometer screen.

 

The OBD 2 needs the reader unlike early versions of OBD 1 , the earlier XJ6 had the OBD 1 codes come up on the instrument cluster

If you place your finger on the # 1 fuel pump relay you should feel 3 clicks in the starting sequence , On - Off - On

The first click on for 4 seconds comes from the ignition key

The 3rd click on for the duration of your drive comes from the crankshaft position sensor

The priming or charging fuel pressure must be trapped in the fuel rail as it is consumed before the 3rd click

You can cycle the key several times to build up a lacking prime pressure or try pinching off the FPR return line

I wouldn't recomment running the RPMs on up in this manor but this process will give you information on if the FPR is bypassing too much pressure back through the return line or a bad check valve in the pump itself

Swapped relays in case power contacts inside are compromised ?

 

I found a bad fuse for my DLC and swapped it out so i now have codes for you guys too help me figure out the issue.
so the codes are as follows
p0303
p1316
p1313

 

see page 121 for a 1997

Misfire cylinder # 3

Misfire excessive emotions

Catalyst damage A bank ( fwd 3 cylinders

http://www.jagrepair.com/images/Trai...20-%202000.pdf

 

Time to play around in the engine bay for a little bit will update when issue is found or fixed

 

Clean the small multiwire ground terminal post ( 2 ) on the rear firewall

Clean the O2 sensor connectors ( 4 ) and do not swap connections as they do

Swap the # 3 coil with the # 6 and see if the codes follow to that position

The # 1 is the fwd most position and this is reverse from the earlier XJ6 engine

 

Will do, thank you.

 

Hi mh.anthony6,

I have found that the OBDII system in the X300 is not very good at identifying which specific cylinder may be misfiring. I once chased a P0303 code for a while only to discover the misfire was actually in cylinder 6, so you may also find that your misfire is in another cylinder or multiple cylinders.

In addition to Parker's good advice, I would suggest that you very carefully disconnect the ignition coils and remove them one at a time and inspect for oil in the spark plug wells. A very common cause of misfires is oil in the plug wells that seeps down the spark plug threads and interrupts the ground path for spark. The oil is due to leaking spark plug tube seals. If you find oil, you will want to replace your camshaft cover gasket and spark plug well seals.

If you don't find any oil, pull the spark plugs and inspect them for fouling. You may as well replace them while you're at it because the correct Champion RC12YC (71) spark plugs are very inexpensive. Don't use any other spark plug.

While your ignition coils are disconnected, carefully inspect their wiring harnesses for cracked or missing insulation that can lead to shorts that cause misfires. A very common point for breaks is in the bend in the harness at the rear end of the engine near the firewall. You will have to unwrap the harness covering to inspect the wires in the area of the bend.

Please keep us informed!

Cheers,

Don

 

The coils will degrade over the usage of the vehicle and cause different problems

Nature of the beast

There are some test for the coil's health

Motorcarmam has a test he does but I don't do because I'm scared of the dark


There are some free things you can do to ensure they have a healthy power source and the timed 6 individual grounds by the ECU

These grounds when " made " allow current to flow through the coils to do their thing

It is this current we'll address with the Papa Indy 1 connector pin # 4 ( White / Pink wire ) as this can get corroded and subject of a TSB

On your 1997 both PI1 and PI61 may both be black

On the coils there is always 12 volts " sitting on " the coils from the fuse # 12 / 10 amp and right engine bay king relay ( ignition positive relay ) . This is also the first power to the ECU other then direct power sitting on the coils

Have you swapped this relay with the one on the left ?







See point 32 on the right side , this is fuse # 12 . Double click on picture . Follow the wire colored in green as it ties into and goes to pin 33 of the ECU