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Discussion Starter #1
Hi guys,

I recently installed my charger in my garage and man oh man, what a beast it has become now. It drives so well and goes like bat out a cave. Literally pins me back to the seat with much more mid range torque. I will do a full review of fitting and my initial thoughts plus dyno results in a few weeks but I have an issue since charging, and hope someone can help me with it.

My cold starts are great / normal but warm starts are not. It hesitates to fire up even though it'll crank. Sometimes it'll keep cranking and not fire up. Sometimes it'll crank a lot more than normal and fire up. One other time, I had to press the gas pedal while it was cranking to get it to fire up but that was an anomaly. If I had a leak in my fuel system the car wouldn't drive so well or it'll misfire or it'll idle rough. But it doesn't it idles around 925rpm.

Some background info:
75.5k miles (owned since 62.5k)
New battery 2 years ago - Bosch AGM 850cca
Batt voltage 14.1v running // 13.1v with IGN on
Fuel pressure is 3.5 - 4bar on idle / 7bar on startup
Fuel pump changed / fuel filter changed / carbon canister changed / fuel cap changed / fuel tank changed / spark plugs changed / new larger injectors as part of ESS kit installed - all in the last 100 miles
Throttle actuators changed

Lots of other preventative things done but this problem has started since installing the charger. I'm confident it cannot be anything big because it drives and runs like a dream. I will be doing a smoke test sometime to check there but can anyone think of anything please?
 

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Discussion Starter #3
I think it may take time to adapt

Best to ask ess
I have asked several times and they've said to reload the tune which hasn't helped. They've also said to check other things but I've already tackled them.

Very interesting situation....

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I might be wrong cause I don't remember exactly, but fuel pressure range should be more narrow around 3.9-4bar. I would double check that on ISTA

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Ive owned a number of cars and once ive modded them heavily eg motors or heads and cam etc ive always had niggling issues starting from time to time depending on ambient temps and elevation etc
Ive learned to live with it as annoying as it can be

But when it runs it never cuts out? I had an issue with mine cutting out (non sc m5 e60) and was from the power pulley
Tuners dont compensate for charging reduction and idle calculations etc
New battery and stock pulleys never had an issue
Spent like $5000 trying to fix that problem
 

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Discussion Starter #6
I might be wrong cause I don't remember exactly, but fuel pressure range should be more narrow around 3.9-4bar. I would double check that on ISTA

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That's right. Pretty sure mine is in that range.

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Discussion Starter #7
Ive owned a number of cars and once ive modded them heavily eg motors or heads and cam etc ive always had niggling issues starting from time to time depending on ambient temps and elevation etc
Ive learned to live with it as annoying as it can be

But when it runs it never cuts out? I had an issue with mine cutting out (non sc m5 e60) and was from the power pulley
Tuners dont compensate for charging reduction and idle calculations etc
New battery and stock pulleys never had an issue
Spent like $5000 trying to fix that problem
When it starts it never cuts out or I'm yet to experience that (hopefully it doesn't happen). Wow, $5k is not a small amount trying to chase down an issue.

At this rate it could be one of many things:

Crankshaft Sensor
Camshaft sensors
Alternator
Battery
Coolant temp sensor
Leaking fuel injector
Etc.

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Discussion Starter #9
Personally id try a battery next

Surely it cant be a sensor otherwise it wouldnt run correctly

how hot is it where u live?
Live in the UK not far from London so currently on average its 55 Fahrenheit.

My battery is 12.1v with ign and 14.1v idling. Does that show its weak?

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Discussion Starter #11
Do you have any fault codes related to the thermostat or the ambient temp sensor?
Hi Hasan, No new codes other than ones i am aware of. I've always had a battery drain sign for a long time and input that down to a faulty CD reader in my CCC coupled with my audio build that I'm sure is drawing more more.

I had the CD reader changed thinking drain problems will go away but no. Even if my car is on tender charger itll still come up with a sign 1st thing and then after a drive itll go away.



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Usually starting fuel table is based on coolant temperature. Try switching out coolant temperature sensor, if that doesn't work, ask him to increase fuel pump function during start up above certain coolant temperature. Interesting find. Please keep us posted. Thank you. Ps. by fuel pump function, I meant increasing fuel delivery.
 

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Usually starting fuel table is based on coolant temperature. Try switching out coolant temperature sensor, if that doesn't work, ask him to increase fuel pump function during start up above certain coolant temperature. Interesting find. Please keep us posted. Thank you. Ps. by fuel pump function, I meant increasing fuel delivery.
This. I bet it's a start map issue.
 

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Not sure if this is at all helpful, as I do not know the E60 fuel system that well, however I had a similar issue with my E53 4.8is, whereby it would start fine when cold but not well (extended cranking) when warm. Turned out to be a faulty check value on the return line.
 

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Discussion Starter #15
Usually starting fuel table is based on coolant temperature. Try switching out coolant temperature sensor, if that doesn't work, ask him to increase fuel pump function during start up above certain coolant temperature. Interesting find. Please keep us posted. Thank you. Ps. by fuel pump function, I meant increasing fuel delivery.
This is interesting. I will be changing my coolant temp sensor this week and have just bought a new crankshaft sensor that will swap too.

I'll do it in step procedure so I know what caused my issue.

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ESS have sent me the same file they sent originally which means they csnt be making the mistake on 3 different ocassions ....

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Not sure what you mean. If their map has an issue, they can send it 100 times and still have the same issue...
 

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Discussion Starter #18 (Edited)
Hi guys,

So I decided in the end to give my car to a specialist here in the UK to deal with the hot start issue. Along the way, we found it had a boost leak - normal! So the first dyno showed 438bhp and I laughed wildly. I told the shop to contact me when there are no leaks. Fast forward 5 weeks later (still don't have my car) we have an update.

The following works have been carried out under my instructions - not because they needed doing but because I'm a firm believer in if its going to cost less in the future, and it's not impacting things majorly on a personal note, then may as well gulp the cost now and be done once in for all!

- Replacement of crankshaft position sensor (preventative maintenance)
- Replacement of all 10 coil pack (preventative maintenance)
- Replacement of Water Pump (with metal impellers) (preventative maintenance)
- Replacement of Thermostat (preventative maintenance)
- Replacement of Coolant temp sensor (preventative maintenance)
- Replacement of Fuel Pump and Fuel Filter as we found the new ones installed were broken thanks to the improper installement of the previous shop (who will be in time, reimbursing me - still need to chase!)

Granted that I fit my ESS VT2 kit but essentially it felt much faster and responsive and so without a dyno or smoke test I was none the wiser.

So the shop called me back to say after replacing all those items, the hot start issue still persists! So he asked me to send my ESS cable/flash tune to them which arrived at their shop today. His theory is that he will update my DME SW to the latest and reload my tune to see if that makes any difference with the hot start issue. I hope it does because the bill is starting to add up!!!!!!!

Secondly, speaking to Jim Colley, he believes this could be hot fuel evaporation at the fuel rail. I totally understand the concept, but fail to understand how the day before it was charged, I never had this problem, yet soon as the charger goes on, this occurs.

One key update is that my kit is actually the 650 VT2 kit not 675. I bought a new kit but old stock and when I got my dyno graph it shows 640bhp at the engine. When I started comparing notes with other friends on the 675 kit, all had about 660bhp on the same dyno, confirming that my kit is indeed the 650. I'm not at all bothered because I got it for a great deal (well, not so much anymore since I've going to end up paying so much in diagnosis and labour) but just wanted to share my experience.

The car will be ready this week pending all being well! I've got a lot of faith in this garage who are an approved ESS dealer and have installed 10 kits already this year.

I'll be back with an update soon, ready to tear up some Godzillas and AMGs!
 

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Glad to hear that your car is getting sorted, albeit slowly. Hopefully you're tearing up asphalt shortly.

Sometimes I long for having another 120 ft/lbs of torque in mine but am reluctant to dump the $$$ into supercharging / all the required supporting mods because of stories like yours and dealing with my own problem children in the past. If I have any luck it's bad luck, and bad luck sucks with a 100k mile plus V10.
 

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I'm sure the experts have checked this - or maybe it's not a thing on this platform - but I had some issues with my E46 like this that were the short/long term fuel trims being set. The alpha-n tune no longer used them (I think) and it wasn't updating them. Had to zero those out and I haven't had any issues since.
 
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