The 75 and ZT Owners Club Forums - View Single Post - MG ZT 1.8T Harsh Sudden Hesitation Followed by Harsh Jerking When Heavy Accelerating

JamieR07 · 17th March 2021, 07:40

Hi all!

nice to see so many likeminded people with great taste in cars! im pretty new to forums to i apologise in advance if i do anything wrong

so, to the issue!

i have an MG ZT 1.8T 53 Plate, the previous engine had no compression cylinder 3 so i decided to get a new engine.

i checked all the engine, no marks or scores in the bores, pistons looked pretty new, i had the head pressure tested and skimmed - all came back ok. did a headgasket, cambelt and water pump, new inlet exhaust and cam cover gaskets, plugs, air filter oil and oil filter. i checked the turbo - all ok, and replaced the oil return gasket.

it has since run a little rough when cold, but idles great when warm.

if you harsh accelerate it gets to roughly 3-4k and there is a harsh hesitation that throws you forward in your seat, the only way i can explain it is harsh hesitation / jerking

this only happens when harsh accelerating, if you slowly accelerate the car will run fine and boost like a goodun.

if you really push it to make the harsh hesitation/jerking happen it brings up the EML which are these codes:

P0445 - Control Purge Valve Short Circuit To Battery/Ground
P0444 - Control Purge Valve Open Circuit
P0234 Refer To OEM Repair Information For Code Description
P1300 Misfire
P0170 Fuel System Adaption Out Of Range
P0300 Random Cylinder Misfire

if you drive it normally after the EML comes on, the EML goes out and the fault doesn't return until you turn the car off and on again

if there is any more information you guys want i am happy to give it!

sorry if i have missed anything!

17th March 2021, 07:40	#1
JamieR07 Newbie MG ZT Join Date: Mar 2021 Location: Dunstable Posts: 15 Thanks: 1 Thanked 4 Times in 4 Posts	MG ZT 1.8T Harsh Sudden Hesitation Followed by Harsh Jerking When Heavy Accelerating Hi all! nice to see so many likeminded people with great taste in cars! im pretty new to forums to i apologise in advance if i do anything wrong so, to the issue! i have an MG ZT 1.8T 53 Plate, the previous engine had no compression cylinder 3 so i decided to get a new engine. i checked all the engine, no marks or scores in the bores, pistons looked pretty new, i had the head pressure tested and skimmed - all came back ok. did a headgasket, cambelt and water pump, new inlet exhaust and cam cover gaskets, plugs, air filter oil and oil filter. i checked the turbo - all ok, and replaced the oil return gasket. it has since run a little rough when cold, but idles great when warm. if you harsh accelerate it gets to roughly 3-4k and there is a harsh hesitation that throws you forward in your seat, the only way i can explain it is harsh hesitation / jerking this only happens when harsh accelerating, if you slowly accelerate the car will run fine and boost like a goodun. if you really push it to make the harsh hesitation/jerking happen it brings up the EML which are these codes: P0445 - Control Purge Valve Short Circuit To Battery/Ground P0444 - Control Purge Valve Open Circuit P0234 Refer To OEM Repair Information For Code Description P1300 Misfire P0170 Fuel System Adaption Out Of Range P0300 Random Cylinder Misfire if you drive it normally after the EML comes on, the EML goes out and the fault doesn't return until you turn the car off and on again if there is any more information you guys want i am happy to give it! sorry if i have missed anything! __________________ Still learning how forums work!