When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
my x300 runs very poor. Id idles bad and its shaking on acceleration. It didnt stall but it has not the power like its meant to be plus its louder.
Please excuse my bad english, im from Germany.
Its a: Jaguar X300 3.2L straight six 1997 it has a LPG conversion, but i didnt use it, when i buyed the car it was allready in, used it for 6 month, but it runs very moor poorly on LPG.
What have been done:
- changed spark plugs: Champion RC9YCC
- oilchange
- compression is fine on every cylinder
- changed coil pack: Lucas Made in Japan
- crank position sensor changed
- airflow meter changed
- throttlebody cleaned
- colant temp sensor changed
- Lambda Sensor changed (i think its calles O2 in english, the two sensors in the exhaust)
- new battery
Im done didnt know what to do from now. It didnt throw any codes even if i unplug something it didnt try to throw a code.
I might be missing something but I watched the videos and it sounds OK to me. Certainly nothing I could hear that would aid in diagnostics. I can't detect any misfire. You may need to be more specific with a description of the problem you have.
You seem to have hit the big ones:
1. You replaced all 6 coils with Made In Japan ones
2. You replaced all spark plugs. (You sure they aren’t supposed to be RC12YCC? They were changed for the 4.0 engine in a TSB)
3. You replaced the MAF sensor.
4. You replaced both oxygen sensors.
The only sensor that could still pose a problem is the Coolant Temperature Sensor. Inexpensive.
I can’t really hear your issue, but I would love to know what your long term fuel trims are. Can you plug into your OBD2 port and see if you have any stored codes?
Is your concern the sound , something is banging like the valve section or a oil pump
t's not a rattle like a un tensioned timing chain
Or a engine response issue ?
Thanks for all the replies, yeah the sound is pretty loud but i wouldnt mind if thats the only problem. Oilpressur is allright. Valves seems like a pretty expensive Job.
Mostly its the loss of power, its like someone holds the car down a bit. Its not missfiring constantly its sometimes. When it stands and i put a hand on the engine its like sometimes theres a hit. Like every 3-4 seconds.
When you sit inside the car and standing in P oder D or N it the same. Its shaking every 3-4 Seconds like its misses cylinder sometimes. Sometimes its worse its shakes for like 10 seconds constantly and the it calms down and then its like normale 3-4 sec hit.
I can try to record an OBD Drive with "torque". I first have to look how i can record it.
The spark plugs are correct, this is a 3.2L for the 4.0L you neee the other champions you have named.
Was the issue present before you replaced all of those parts, and has it remained the same throughout?
Dis the issue develop during your ownership of the car or did you buy it with the problem?
If the issue started during your ownership, did it start suddenly or gradually and get worse?
What MAF sensor did you use? Is it an OE unit or a cheap ebay MAF?
At the moment I am thinking I'm thinking you might have a Fuel Pressure issue. Do you have a means of testing Fuel Pressure?
You really need to get some diagnostic information before throwing more parts at it. As @Vee said get some live data from OBD as a starting point, and some readings from MAF, Temp Sensor etc.
There is a thing where the electrical connector on the transmission body gets dirty as it communicates through the transmission ECU to the engine ECU things like the it's own transmission rotation speed sensor value
This seems to effect the engine regulation at low RPMs in the gear shifting times or regime
The location of this connector is located on the left rear of the transmission and may be able to get to without jacking the car up
The connector is not a twist off and on but like a air hose that pushes off and on engagement
The transmission on the 3.2 kiter should be a ZF4HP22 and not a 24 used on the 4.0 liter version
The difference between the 22 and 24 is ...........
Also to look at is the big ground wire from the starter / engine block mounting bolt to the car frame , this causes many problems in engine regulation . Best worked on from the bottom side . 15mm socket on the starter bolt and 8 or 10 mm on the car frame bolt . put some light bulb grease on the car frame surface after wire brushing it clean
Editing
On your Torque device the items to look for are :
MAF - at idle should be about 3.5 grams / second and this value can be off by a multiplication factor of 10 because of a ELM - 327 device's software error
TPS - at the idle mechanical stop will read around 11 % and never 0 % like you would think . Watch for a " smooth " increase as you " slowly " increase throttle opening
RPM
Short term fuel trim or STFT - This will be around 8.0 % with a cold engine before it goes to a target value of 0.0 % after the ECU goes to " closed loop " mode dependent on the ECT reaching a certain temperature . This target value of 0.0 will try to stay 0.0 as your throttle up the engine
ECT - watch for a climb in temperature
Last edited by Lady Penelope; 02-27-2019 at 06:54 AM.
If you have the torque app, I'd like to know:
1. What is the LTFT (Long Term Fuel Trim) on both banks.
2. I'd like to know what the coolant temperature is as well, although I think there is a sensor and a sender, so this might not be helpful.
3. See if you can tell me what the MAF is doing as you're driving. Where is it at idle and what happens to it while driving.
Was the issue present before you replaced all of those parts, and has it remained the same throughout?
Dis the issue develop during your ownership of the car or did you buy it with the problem?
If the issue started during your ownership, did it start suddenly or gradually and get worse?
What MAF sensor did you use? Is it an OE unit or a cheap ebay MAF?
At the moment I am thinking I'm thinking you might have a Fuel Pressure issue. Do you have a means of testing Fuel Pressure?
You really need to get some diagnostic information before throwing more parts at it. As @Vee said get some live data from OBD as a starting point, and some readings from MAF, Temp Sensor etc.
Hi,
so when i buyed the car it runs like a dream, for a while, the problems started about 3 month ago.
The problems got worse, first it was just like a little shaking on acceleration between 70-90km per hour, so i changed the MAF, with a used unit, it worked.
Then it get worse again so i buyed more used MAFs, in germany i never found a new original MAF, only used ones, so i have to stay with them, but i didnt think that every one of them are broken.
Now i changed coil packs, with the made in japan Lucas Brand, all six, problem was better.
Then get worse again.
Then i changed every other listed part.
But it didnt do anything for the engine. So maybe its damaged or something like this, but i dont know.
I can go to a shop and let them check the fuel pressure. Maybe i can do this next week, most shops are pretty busy right now.
Maybe it gets some air after the MAF, but i dont know how to check this. Beacause when i simulate it by taking off the little tube after the MAF that goes to the valve cover, it would suck some air in it... but the engine dont do anything when i do this.
So I will check the Fuel Pressure and let them do a compression test again, but i can get that results just next week.
Until then i will try to setup my torque app and get some readings.
Im very thankfull for everyone who is helping. Great community.
i found a shop that could do a compression test today...
Cylinders have between 8,5bar and 9,5bar (123psi to 137psi, thats what the googleconverter says)
Disconnect the MAF from the filter cleaner and wrap the MAF opening with plastic wrap, so it's air tight. You can reconnect it if you want at this point, so that the plastic is held in place. We want to seal off the intake from just after the MAF. Disconnect the hose from either the camcover or the intake elbow (preferably from the camcover first). Take a cigar, cigarette, or whatever, light it, take a puff and blow it into the hose you disconnected. Keep blowing smoke, and blocking the hose with your finger while drawing another puff. If you are taking the hose off from the camcover, you should be able to blow in about three breaths of smoke. After that, you either cannot push anymore air into the system and you should be able to find a spot where smoke is leeching out. It will be difficult to notice if it's coming out of the intake manifold gasket, but try to see if you can see any smoke coming out. The other common failure point is at the idle air control valve (IACV). A vaccum leak at my intake gasket caused me some serious headaches until a mechanic finally found it! (I don't believe I ever tried this smoke test back then)
If you blow from the intake elbow, then you're testing the gaskets around the camcover and spark plugs for leaks. While youre there, make sure none of the spark plug wells have filled with oil or water? A failing spark plug gasket can also cause these problems, but you'll know if there's a problem when the cylinders are oily.
Other than that, please make sure your battery is showing 14v through the torque app. A dying battery also causes problems, a good indicator is usually when your power locks start to act up.
Please report back on the LTFT, Coolant Temp readings, and MAF readings. All of those will help find the problem.
The factory document for compression test at 300 RPM starter speed is 110 to 117 PSI
This is when someone sent me a copy of the document
My personal opinion is a recheck of the compression is not needed
Fuel pressure with engine not running or at idle is 43 PSI , this 43 goes up 3 or 4 psi on throttle up by a vacuum hose on the back of the fuel pressure regulator
The fuel pressure test point is on the fuel rail only
Look for the short hose to be installed and air leak test the FPR diaphragm , but not too much test pressure as may harm it
This is for liquid gasoline
Last edited by Lady Penelope; 02-27-2019 at 01:07 PM.
Wow Guys, i have to thank you all very much, im absolutly flashed with all the help you are providing.
I will try to check all the things in on my weekend, i think i need alot more time to Test these things, im not very used to do this stuff, but i will try my best.
Tomorrow i will check the things with the Torque App and provide some data. Im happy that the compression seems okay so the engine is healthy enough to survive this hard time.
i have done a reading with torque, i uploaded the ride.
What i found out: Yesterday the mechanic told me that one sparkplug was black on cylinder 6 the closest to the windscreen. I looked at the 1500km old ignitioncoil (Lucas Brand) and it has a small crack, i dont know how this can happen after that small amount of kilometers, I will Order a new one... Maybe it will make the problem a little bit better.
https://youtu.be/kuFWdGCXc1c
I will still try all the things you told me on the Weekend.
The coil will swell , expend , and crack after it heats up
This will cause arcing to the coil well walls during ignition cycles
Altho the valve cover is electrically isolated by the shouldered plastic mounting bolt washers , it's not 100 %
This pulse will be picked up in the electrical wires of the car which before great effort was made to be a smooth flat line DC signal
More that one electrical signal can exist in a wire at the same time , this is referred to as " dirty electricity "
once the ECU sees this dirty electricity it doesn't function properly
Film observations :
Your coolant temperature is slowly rising
Long term fuel trim on both banks stays at 8 % , is the ECU staying in " open loop " or rich mixture . The rise in temps should trigger a change at a point by design
At 4:20 in your film the short term fuel trim on both banks goes nuts , the target is 0 through all throttle and engine load ranges . This 0 target should not be in error more the the value of 3
You MAF does not make sense even if multipleyed by 10 to account for device software error
With your foot off the pedal does the TPS read 11 %
Last edited by Lady Penelope; 02-28-2019 at 04:51 AM.
So Bank 2 is a disaster. Your STFT maxes out for much of the video. Guess which bank Coil #6 is? That right! Bank 2.
You seem to have at least 2 problems.
The second problem is your long term trims are both high at 8. You either have a vacuum leak (remember the post I made about blowing smoke into the intake?), or your TPS is bad. If your mechanic friend is so inclined, ask him to make sure there are no vacuum leaks, especially check around the intake manifold. Long term trims indicate that you have a leak somewhere. With the way the oxygen sensors are looking, you could have a major exhaust manifold leak perhaps? Take that shield off and see what things look like before the lambda sensors. No one cares about anything after that, as it won’t affect anything the engine sees. I suspect it’s the intake manifold though, IF there’s a leak.
I had an issue where my long term trims we’re constantly in the 7-10 range, and it was the Throttle Poteniometer Sensor, even though it was bench testing perfectly. It is an expensive part, but as soon as I replaced that, my long term trims dropped to zero.