Help guys-- a little history about 3 months ago I changed tensioners & chains on my 1998 XJ8 with 64,000 miles.. About a year ago the Jag dealer reprogrammed for the Throttle Body issue. I assume disconnecting the battery would not require another reprogram of the TB.
Jag has run well since Tensioner & Chain update --until Now, about 400 miles later, I got the DTC P1396 , P1000, and P1643 codes. everything seems to run fine.... I have cleared the codes twice with the Hard Reset, disconnected battery, then same codes returned after about a day of driving. I have the Jag CD, but i do not see any impederce/resistance or voltage checks for the
V V T solenoids ? or Bank "B" faults associated with P1396.
The P 1643 code - I think is for either Fuel pump monitor low output or a Transmission Fault.

I need your help and would appreciate your - expertise,and experience on troubleshooing this issue.

Thanks for listening and I will keep you all updated on progress and results.

 

1396 is for vvt failure or circuit failure.. check the connection at the vvt ..for drivers side . i wud disconnect the vvt and put a pin in the connector shorting it out.. and then if you get 1398 code then you wud know the wiring is good.. its probably just a vvt failure... you can check it by removing the two 8mm bolts and see if anything looks odd in there . i know there like 300-400 i priced one out like 2 weeks ago.. sometimes the connector breaks on them..as well

for the other code you will need to check the connections at TCM may need a new tcm.. which also is expensive.. on theCAN network the TCM is bascially not giving the thumbs up .. on the network..

 

First---- Thank Jag-G very much for the expertise. I did check the resistance on the VVT coil earlier today and it read about 10 ohms,
so the Coil and the coil contacts seem OK Does-- this resistance looks OK ?? Your opinion on this would be appreciated.
I know thii does not mean the mechanical parts of the VVT are OK. When or if I need to remove the Coil to inspect inside the VVT what should I see to indicate I need to replace it Could I have installed it wrong when the Tensioners and Chains were replaced ?

Question -- Before I short accross the pins on the VVT harness socket going back to the ECM. Can you tell me if I should clear the CODES Prior to this and-- can I drive the vehicle with the VVT Harness pins to the ECM shortrd to see if the code comes back on.

Typically I can drive all day then when I park the XJ8 overnite and drive it a block or two the next day is when the codes reappear.

With help from you I would like to get the P1396 code cleared first then attack the P1643 --TCM.

I plan on cleaning the contacts and check voltage on the TCM tommorrow as well.


Thank you Again

 

Jag-G --I was not able to complete the VVTtest with the Jumper on the VVT terminals

Well folks, Murphy's Law is alive and well. My OBD II has a problem.... The "CEL" is still on-- the OBDII linked up but did not detect the codes or the "CEL". I am taking it to the auto zone tomorrow.

I went ahead and continunity checked the VVT solenoids and cable back to the EMS. No problems found-- booth VVT solenoids read 10 to 12 Ohms each. On the VVT Plug B+ terminal Voltage is 12 volts.

More good stories tommorrow, I hope

 

In hat case your VVT is blocked or has a mechanical failure.
Possibley the screen is blocked not allowing oil into VVT.
You need to clean it out if blocked, but more likely you need to replace the VVT solenoid.

 

i wud remove the vvt just 2.... 8mm bolts.. and see if it is clogged.. but looks like you need one.. there about 300-400

 

FJT and Jag-T thank you for the feedback and Tech support. As I posted earlier my OBD II is being sent to the factory for warrant repair--tha slowed me down. I went to Auto -Z the P13--
codes are still their but -- thankfully for now the P1643 code is gone.

I am into the VVT Solenoid. I removed the 2-bolts from the front of the "B" bank ---used my trusty mirrior to visually inspect-- there is some oil film on the surface of the housing. I am not sure what else I should be looking for or do.

Is it possible just the VVT Solenoid plunger is sticking?
Should I just pull the guts out and put a new one in?
What part pieces should I see or be concerned with? Any flush or cleaning recommended?

Hopefully it is not the Valve Timing Unit attached to the cam!

Please let me know what you would do next--- and if changing out theappreciate

 

Sorry the send button was hit before I could finish Last Post...

So if flush cleaning the VVT solenoid does not remedy situation. Can you suggest a couple part sources?

Thanks again crpace@***.net

 

At the bottom of forum list there is vendors listed.

 

Sorry I haven't been following this too closely, and I haven't seen any V V T or V V T solenoid failures. If there is a different DTC for each solenoid fault, I would try swapping them and seeing if the code followed. Maybe there is only one code, since that engine only has one cam position sensor for B bank, I don't know. I 'm pretty sure you can't test the V V T unit itself to see if the retractor spring is insufficient unless you pull the front cover and at least loosen the primary chain tension so you can try to rotate it.

I have solenoids And V V T's I can test if you need any other information in that reguard.

 

Folks Just call me lucky. Code cleared and CEL OFF> for over a week.
All continunity/resistance checks of the connections and wiring from the VVT solenoid electrical connection to the associated EMC - EM 14 and EM 15 CONNECTIONs were good. Code came back on after 2 days.

I had not checked the CAM or Crank Sensor Wiring. I had only previously checked the sensors.
I checked continunity, resistance and voltage form the Cam sensor to the EMC - EM13 Connection.

Problem was probably a poor connection/contact of the pins in EM 13 connection that the CAM and crank sensor communicates with the EMC.

1998 XJ8 running fine with no codes for 13 days I hope thats a luky number.

Tip that may be useful to someone---Going through the wiring I discovered that when the CEL is on the EMC will not allow the VVT solenoid to activiate.
IF the CEL is OFF and the Engine at idle the EMC will activiate every 5 minues like clock work and if the VVT does not recieve oil pressure or move ( this is sensed by the cam sensor) the P1396 code will come on as well as the CEL.

Thanks for everyones input.

 

where is the cam pos sensor on a 98 xj8 4.0 ?

 

Sensor is located on the Driver Side, on the rear of the Engine head/sparkplug-coil cover.
You will see an Electrical connector attached.
Sorry for the late responce