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Misfire Cylender 4 Low Compresion after flashing SES and p0300

1K views 7 replies 3 participants last post by  ThumperPup 
#1 · (Edited)
Ok so i know this car is trying to tell me something like its time to let me die but im not going to do that
if i do anything im going to make sure it gets fixed and then sell it or keep it
doesn't matter to me but not letting it go to a bone yard

Ok so here is what is going on
yesterday i went to the shop ok no not yesterday it was Monday i had done WOT"s and the Oil Consumption still was not getting better was still at 1-qt every 900-100 miles and it went from getting 1700 miles to a qt right down to 900-1000
so Mechanic pulled the plugs to check them see if they where good or any signs of anything wrong from the plugs i guess
and nothing he cleaned them up put them back in car started up fine i drove away 5 miles down the road i got the Flashing SES lite pulled codes P0300 Engine Misfire detected called him told him what just happened

he had me come right back he check with his computer was telling him cylinder 4 was Misfire he pulled the plug again checked the boot all was good put it back in was running fine about 2 hours latter
i was at a stop light went to put my foot on gas and SES came back on i felt the a Hesitation when i put foot on gas

called him told him what happens he said bring it back ill have to leave it over nite for him to find out whats going on

He calls me yesterday saying
he put new plugs and new boots still having trouble he did a fuel Injection cleaning still having trouble
this morning he tried a new Coil pack still having the same problem
right now he is doing a Full top end cleaning
said if it does not get better after this he is not sure where to go next other then dropping the engine pulling the heads and looking at the pistons and rings see if something is wrong in there



He also mentioned that when he had it hooked up to his Fuel Injection Machine it was running fine did not have any misfire but when he took it off the machine and hooked the fuel line problems started again
He also ruled out any problem with the fuel pump or or in the line because he did the fuel pressure test and it was fine

anyone have any suggestions i could run by him he is always open to learning new things that could be bad and is always open to other ideas not closed minded like he knows everything so if i find something out here i can tell him and see what he thinks please help

Thank you
 
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#3 ·
he didn't tell me exact results but he said after he did the fuel Injection the first time the Compression in cylinder 4 got a little better but its still lower then it should be
and its only cylinder 4 that has the problem
right now he still got everything soaking for the full top end cleaning said he will call me tonight ones that is done and let me know more

But he said only problem is with Cylinder number 4 all the other cylinders are firing fin just as they should
 
#5 ·
I don't know but i know he told me that it was on for about 45 minutes before i called him yesterday to ask what was going on he had mentioned he was going to leave it on longer before we got of the phone
ill wait till i heard back from him and also mention and see if he has done a leak down test like you suggest i know he has done alot already
 
#6 ·
My Mechanic just called me a few minutes ago yes at 11PM at nite

i was like yo your still up he said yeah i been working on your car non stop since Arly AM
he said he just got it all buttoned back up did the full top end Cleaning and so far its running smooth first time he fired it up he said it had a slight stutter hesitation a bit but just for a few seconds but for the past hour and half or so its been running and idling Smooth no hiccups not nothing at least nothing that it shouldn;t be doing he said

but won't said don't come out tonight lol he wants to go home and sleep
he said he will call me first in the AM when he gets in and if it starts up all nice and good then he knows its ready
 
#8 ·
Mechanic did a fuel Injection cleaning still stutered after that
then he decided after checking several things changing plugs again known good coil pack he had
new boots and not sure what els
he decided to do a full top end cleaning he let the cylinders soak for about 9 or 10 hours i think
did a fuel injection cleaning again and an oil change and fired it up and ran smooth as a fresh black top highway
 
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