Topic: jeep grand cherokee:Running rough and strong smell of petrol (Read 13422 times)

PtP · « **Reply #25 on:** May 24, 2009, 09:56:51 AM »

Quote from: "bunnykins"

its all too technical for me, whats MAF, TPS, CPS ? thanks

Here goes:

MAF – Mass Air Flow Sensor
http://motors.shop.ebay.co.uk/items/_W0 ... acat=14239

TPS – Throttle Position Sensor
http://motors.shop.ebay.co.uk/items/_W0 ... acat=14239

CPS – Crankshaft Position Sensor
http://motors.shop.ebay.co.uk/items/_W0 ... acat=14239

Also, just put into google any of the above terms and you’ll plenty of information as to what each sensor does.
http://www.google.co.uk

Mike Pavelin · « **Reply #26 on:** May 24, 2009, 10:26:24 AM »

I still say do compression check before wasting time and money on other stuff.

bunnykins · « **Reply #27 on:** May 29, 2009, 09:01:40 AM »

the car has been in with mansfield 4x4 since 22.05.09 and they say there was no error code and the only thing they can find is a small hole
in the exhaust manifold. i have asked them to weld it but they say it may not work and advice me to buy a replacement manifold and prob 3
hours to fit. so i am not sure if they have done a compression check. they did say they did a reset [ not sure what ? ]on it after i changed
the lambda sensor.

why cant it be welded ? if it can, how long would that take to do ?

thanks

Mike Pavelin · « **Reply #28 on:** May 29, 2009, 09:13:01 AM »

It may be weldable but is likeley to crack again and the labour time would be more as it has to be removed to get at the bit that cracks. Replacements are available for around £100. However, unless it is a huge hole it is not likeley to be causing your problem, there are plenty of 4.0 Jeeps running round with cracked exhaust manifolds (it's very common) with no porblem at all. Is the misfire a regular one on one cylinder only? if it is, I would still get a compression check done if nothing elese can be found. Computers are fine but they cannot see mechanical faults. It only takes 10 minutes and will eliminate a burnt valves, damaged piston, blown head gasket straight away.

bunnykins · « **Reply #29 on:** May 29, 2009, 10:42:48 PM »

Quote from: "Mike Pavelin"

It may be weldable but is likeley to crack again and the labour time would be more as it has to be removed to get at the bit that cracks. Replacements are available for around £100. However, unless it is a huge hole it is not likeley to be causing your problem, there are plenty of 4.0 Jeeps running round with cracked exhaust manifolds (it's very common) with no porblem at all. Is the misfire a regular one on one cylinder only? if it is, I would still get a compression check done if nothing elese can be found. Computers are fine but they cannot see mechanical faults. It only takes 10 minutes and will eliminate a burnt valves, damaged piston, blown head gasket straight away.

i'll ring them tomorrow and ask them to do a compression check. i have not seen the hole so not sure how big/small it is. it not really a misfire, but a hesitation on accerelation or under load like going up a hill or when the autobox change down a gear. when i changed the plugs they were all covered with black soot like the front lambda sensor that i changed. hope they have also checked the after cat sensor.

thanks for taking the time to help out with feedback, much appreciated.

bunnykins · « **Reply #30 on:** June 09, 2009, 10:15:11 PM »

got my jeep back today - 5 hours = labour 3 hours for the manifold and 2 for diagnostic.£270.00 i supplied the manifold.

not happy, it still seems rough and does not seem to be as quick or responsive as before, perhaps i need to give it time to run in ?

they carried out a compression test :
1=90psi
2=95psi
3=95psi
4=90psi
5=100psi
6=105psi
does this look ok ?

thks

bunnykins · « **Reply #31 on:** June 12, 2009, 11:00:29 PM »

well i took the jeep back today and mansfield put the old lambda back as a test. i drove it and within minutes it started to jerk about so i went back to
mansfield. i left the jeep there while they swap the bosch one back. they tested the old lambda and that definately dont work.

but the bosch one that i bought works fine ......... except it is running a little rough and does not seem to work well with the overdrive button switch off.
is it true that only the jeep ones will work 100% ? or is something else amiss ?

anyone know how much the jeep lambda is from the jeep stealers ? and is it cheap to buy from US ?

thks

Bishops Finger · « **Reply #32 on:** June 12, 2009, 11:40:19 PM »

What did Mansfield think....

PtP · « **Reply #33 on:** June 13, 2009, 11:32:50 PM »

Quote from: "bunnykins"

........is it true that only the jeep ones will work 100% ? or is something else amiss ?..............

I've recently had a Bosch one fitted to my TJ and whilst the old one with hindsight was okay, the Bosch one seems to be working just fine.

Panic mechanic! · « **Reply #34 on:** June 14, 2009, 08:47:34 PM »

your jeep system is a bosch system from what i understand so it's the same.

Mike Pavelin · « **Reply #35 on:** June 15, 2009, 07:27:17 AM »

If you have been running with a faild lambda sensor for a while, have you considered that the cat could have partially melted inside due to over fuelling. Whis would create a restriction in the exhaust resulting in power loss and incorrect fuelling at higher revs.

JamesH · « **Reply #36 on:** June 15, 2009, 10:18:05 AM »

New lambda from Jeep was £80+VAT for my XJ last month and new cat was £65+VAT & delivery from catsdirect.com

bunnykins2 · « **Reply #37 on:** July 03, 2009, 08:18:57 AM »

Quote from: Mike Pavelin on June 15, 2009, 07:27:17 AM

If you have been running with a faild lambda sensor for a while, have you considered that the cat could have partially melted inside due to over fuelling. Whis would create a restriction in the exhaust resulting in power loss and incorrect fuelling at higher revs.

so i suppose the cat and the after cat sensor now have to be replaced ? is this normal ?

does the compression figures look healthy ?

thks

bunnykins2 · « **Reply #38 on:** July 03, 2009, 08:23:22 AM »

does anyone know if the computer needs to be reset if you change/fit a diferrent lambda sensor ?
or do you just fit it and the computer will automatically work out the mixture and it will reset itself ?

i just had the jeep mot'd and it passed ! they found 2 screws loose on the new manifold that was fitted
and tightened them up which may affect the mixture ?

thanks

Mike Pavelin · « **Reply #39 on:** July 03, 2009, 08:10:09 PM »

It will relearn itself eventually.

bunnykins · « **Reply #40 on:** August 09, 2009, 08:32:48 AM »

thanks for all the feedback.

well i am not totally happy since my jeep came back from mansfield, as its not running as smooth as before it went in,
despite them saying i needed a new manifold and the sensor. they havent replied to my email or shown any interest in
helping me sort this out.....they were happy to take the money !

i replace the leads,distributor/rotor/plugs with all new. i have heard that some leads will not work as well as the oem
stuff, has anyone had this ? i feel like putting the old leads back to see if its that.

any ideas are welcomed.

Bubba · « **Reply #41 on:** August 09, 2009, 11:03:23 AM »

leads can and indeed do breake down

bunnykins · « **Reply #42 on:** August 10, 2009, 10:10:57 PM »

Quote from: V8 Bubba on August 09, 2009, 11:03:23 AM

leads can and indeed do breake down

do you mean the old or the new ones ?

daggie · « **Reply #43 on:** August 12, 2009, 06:55:51 PM »

where abouts are you BK??

bunnykins · « **Reply #44 on:** August 15, 2009, 01:05:31 AM »

Quote from: daggie on August 12, 2009, 06:55:51 PM

where abouts are you BK??

suffolk

Author Topic: jeep grand cherokee:Running rough and strong smell of petrol (Read 13422 times)

Mike Pavelin

bunnykins

Mike Pavelin

bunnykins

bunnykins

bunnykins

Bishops Finger

Panic mechanic!

Mike Pavelin

bunnykins2

bunnykins2

Mike Pavelin

bunnykins

bunnykins

bunnykins