Anyone have any ideas on this problem? FINALLY SOLVED

[Leigh_bullitt]

Cheers that’s a good point.
How could I log the crankshaft sensor on FORScan?. What would I be looking out for ?.

thanks

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[Leigh_bullitt]

I did actually perform a crank relearn about a month ago.

 

[sk47]

how to test a crankshaft position sensor - Search

Hello; found this. May need to remove the sensor for some checks.

 

[Leigh_bullitt]

Also have the adaptive learning switched off on the tune. LTFTs disabled. But this isn’t causing the issue either as it does I. Stock form too.

 

[AZ_Ryan]

Does it stock or tuned.
everything seems fine at the intake and idles perfectly.
it’s really strange..

Sorry but what does this mean?

 

[fast306stang]

Does the problem only occur during the cold months or does it do it year-round?

 

[Leigh_bullitt]

Hi
It does it regardless of the weather outside hot or cold.
literally today went for a drive from cold and it just didn’t feel right. More engine noise than normal, exhaust tone was weak, surging when trying to hold the throttle at a certain point.
went to eat for about an hour and even when I started the car I immediately noticed it sounded better. Engine was quiet and it was pulling hard again.

 

[Leigh_bullitt]

Could it be something to do with the oil temp and the VCT solenoids ??

 

[sk47]

Hi
It does it regardless of the weather outside hot or cold.
literally today went for a drive from cold and it just didn’t feel right. More engine noise than normal, exhaust tone was weak, surging when trying to hold the throttle at a certain point.
went to eat for about an hour and even when I started the car I immediately noticed it sounded better. Engine was quiet and it was pulling hard again.

Hello; You may have written about this but refresh my memory. I get that it runs rough from startup and while cold. That the car runs good after it gets warm and is shut off for a short time to an hour.
What i wonder is if starting from cold and if you kept driving for say 30 minutes without shutting the engine off. Will the engine ever get to running good during a long drive from cold? What i have gotten so far is the engine only gets smooth after a restart. Is this the condition?

Were this an older car with a carb and a mechanical choke I would be suspicious of the choke. I have had older Fords which ran rough till warmed up. But the cold start is controlled by the computer (ECU I guess). I do not have much of a clue. The computer will get temperature readings from sensors so should run things a bit rich at start up. But the EPA wants the cats and other running parameters to get to operating temps as quickly as can be. Oxygen sensors often have, I think, ways to get them warmed up.

I suppose you have tried simply removing the battery cables for an hour. That has "fixed" the occasional problem for me and others.

 

[Leigh_bullitt]

Hi
Yes exactly that.
First cold start of the day and it will run like most cold engines. Feel a little hestitant until it warms up.

but I could drive the car for a good hour from the first start and it will continue feeling rough. The. I stop the car for about 30 mins start it again and it’s much smoother.

also though it doesn’t happen all the time. It may continue running rough even after re starting sometimes.

best way to describe how the car feels is that it’s running from an inicial cold start all the time until it suddenly decides to smooth out. It’s really weird.

yes I’ve done Kam resets and pulled the battery too to no avail.
I’ve also data logged the temp sensor and it will show a steady 88 degrees ( C ) when warm. So the car isn’t thinking it’s cold all the time.

but yes your right it almost feels like the choke ( older cars ) is always on.

 

[AZ_Ryan]

Hi
It does it regardless of the weather outside hot or cold.
literally today went for a drive from cold and it just didn’t feel right. More engine noise than normal, exhaust tone was weak, surging when trying to hold the throttle at a certain point.
went to eat for about an hour and even when I started the car I immediately noticed it sounded better. Engine was quiet and it was pulling hard again.

Do you have a tune? Any mods? Manual or automatic?

 

[Leigh_bullitt]

It’s a manual.
yes I have a tune, but problem is still their in stock form.
only mods are borla s type cat back.

 

[AZ_Ryan]

This might help-

https://www.mustang6g.com/forums/th...circuit-range-performance-malfunction.139011/

 

[sk47]

Hello; May be time to do some basic engine function checking. Modern engines are regulated with computers which make decisions based on inputs from sensors. Many of these electronic systems throw codes when out of range.
The engines are still analogue in operation. There are things such as chain tensioners which best as I know do not throw codes. Ther have been threads about chain tensioner problems.
There are cam phasers which run on oil pressure.
If the fuel rail has a suitable fitting a pressure gauge can be fitted to check fuel pressure when running and also if the fuel rail holds proper pressure for hours after the engine is shut off.

Good luck.

 

[Leigh_bullitt]

Hi All
I think I may be on to something ?????

ok so I took the car out today. Same thing cold start drove ok. A little stumbling but normal I guess for a cold engine.
it stayed that way for driving for an hour or so.
I left the car for an hour and the difference was incredible. Almost like I’ve never driven the car in this way before.
the exhaust note was deep and rumbling the throttle was as smooth as silk and best way to explain it was everything was running with each other in unison.

but….. I did not this. I was looking down at the rpm gauge and too my ears I would say I was at 5k rpm like when it’s running rough but I couldn’t believe my eyes the rpm was at 2k rpm.

do you think it could be the speed sensor that is giving me problems ??? Or something similar ??

thanks for your help and input

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