Down shift, check engine light, V8 grumble, power loss, and a burning smell. (20 sec)
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Lane - Then put things on hold.
Please do me a favour. Run two tanks of fuel back to back with Techron concentrate. We might have a dirty injector here.
Please do me a favour. Run two tanks of fuel back to back with Techron concentrate. We might have a dirty injector here.
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From: Orlando, FL
C240
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C240
I just came back from filling up, adding a healthy dose of techron.
On my drive, everything made great sense. Perhaps, since my car wasn't driven for two or so weeks, cylinder four's injector became partially clogged, returning my misfires. I guess the injector wasn't very clean to begin with when the misfires before I left came along.
Results to follow. I'm making many trips today!
On my drive, everything made great sense. Perhaps, since my car wasn't driven for two or so weeks, cylinder four's injector became partially clogged, returning my misfires. I guess the injector wasn't very clean to begin with when the misfires before I left came along.
Results to follow. I'm making many trips today!
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Run through 2 tanks of fuel & see what happens otherwise it's back to the list above. Injector deposits take a little while to remove.
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W206 PHEV AMG
or it could be the injector simple needs to be replaced...
I had a issue with throttle position sensor glitch two nights ago, so don't feel too bad. lol
start the car, puts it in reverse back out the garage and driveway, puts it in drive, notice no power, figure it is a tranny slip from not grabbing the gear since it has happened before, down-shift, waited, and go, and 10ft later the engine just shuts off.....
restart the car, throttle blips by itself as if it's gasping for air between idle and 1200rpm, restarted couple more times and back to norm.
no error codes...although i do think my fuel pump is possibly dying which is the only conclusion i can come up with for that symptom.
I had a issue with throttle position sensor glitch two nights ago, so don't feel too bad. lol
start the car, puts it in reverse back out the garage and driveway, puts it in drive, notice no power, figure it is a tranny slip from not grabbing the gear since it has happened before, down-shift, waited, and go, and 10ft later the engine just shuts off.....
restart the car, throttle blips by itself as if it's gasping for air between idle and 1200rpm, restarted couple more times and back to norm.
no error codes...although i do think my fuel pump is possibly dying which is the only conclusion i can come up with for that symptom.
Last edited by FrankW; Jul 17, 2010 at 08:59 PM.
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From: Orlando, FL
C240
or it could be the injector simple needs to be replaced...
I had a issue with throttle position sensor glitch two nights ago, so don't feel too bad. lol
start the car, puts it in reverse back out the garage and driveway, puts it in drive, notice no power, figure it is a tranny slip from not grabbing the gear since it has happened before, down-shift, waited, and go, and 10ft later the engine just shuts off.....
restart the car, throttle blips by itself as if it's gasping for air between idle and 1200rpm, restarted couple more times and back to norm.
no error codes...although i do think my fuel pump is possibly dying which is the only conclusion i can come up with for that symptom.
I had a issue with throttle position sensor glitch two nights ago, so don't feel too bad. lol
start the car, puts it in reverse back out the garage and driveway, puts it in drive, notice no power, figure it is a tranny slip from not grabbing the gear since it has happened before, down-shift, waited, and go, and 10ft later the engine just shuts off.....
restart the car, throttle blips by itself as if it's gasping for air between idle and 1200rpm, restarted couple more times and back to norm.
no error codes...although i do think my fuel pump is possibly dying which is the only conclusion i can come up with for that symptom.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Lane - an injector is not hard to replace but at your mileage it is way below injector cycle life - more likely dirty from crap American fuel - & it is crap because you guys want it cheap - same as SA. If we all ran Euro fuel we would have no trouble.
Let's try & clean injectors first. 2 tanks with Techron concentrate will take the injector back to as new clean. If it then gives crap then maybe replace.
Long before then - you have not answered when last your car had a fuel filter & before we mess with fuel pumps we need a fuel rail pressure test.
Let's try & clean injectors first. 2 tanks with Techron concentrate will take the injector back to as new clean. If it then gives crap then maybe replace.
Long before then - you have not answered when last your car had a fuel filter & before we mess with fuel pumps we need a fuel rail pressure test.
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From: Orlando, FL
C240
I have never replaced it. I bought the car at 56k miles. Should I replace it for good measure?
And what can explain the 50 miles of trouble free wide open throttle spirited driving, and then misfires to follow later? It baffles me!
And what can explain the 50 miles of trouble free wide open throttle spirited driving, and then misfires to follow later? It baffles me!
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C240
Here's a pic of the a cylinder four plug. I took both out, the other seemed normal. Second one of cylinder four seems a bit dirty, or maybe I'm just not a pro reader of spark plugs. Did I not give enough torque to the plug, perhaps?
Last edited by laneshift; Jul 18, 2010 at 12:51 PM.
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From: Camas, WA
2007 C230SS; 2014 ML350 BT
You are due for fuel filter replacement. It is due every 65K miles/5 years. Mtnman posted a great DIY on it.
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From: Orlando, FL
C240
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Like this
From what I can see at the moment things look OK but I can't read the plug properly.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
A new fuel filter will ensure proper fuel rail pressure at the injectors & give your fuel pump an easier time. This will help ensure that all injectors provide the correct amount of fuel. No 4 injector might be slighly clogged & with low fuel pressure we have a misfire when you place demand on the engine.
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From: Orlando, FL
C240
A new fuel filter will ensure proper fuel rail pressure at the injectors & give your fuel pump an easier time. This will help ensure that all injectors provide the correct amount of fuel. No 4 injector might be slighly clogged & with low fuel pressure we have a misfire when you place demand on the engine.
Again, thanks for being such a supportive bunch!
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From: Orlando, FL
C240
One tank of techron treated 93 octane fuel down. I'm weary of going past 4k rpms. I got three misfires in a row doing that. I had to shut off the engine, stop at the side of the road, and restart, every time, or the grumbling noise and power loss would persist.
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From: Orlando, FL
C240
P0304 is the only code I get one after the other.
The low grumble noise is basically the engine bogging down. Power is lost. The car must be restarted to regain power and the noise goes away. If it's still confusing to understand, I can take a video.
Car starts fine. Upon startup, there is no pop pop pop from the exhaust, it's smooth. When the car is fully warmed up, it's only slightly choppier.
I'm getting a loud, loud belt whine. Sounds like I have an unmuffled kompressor. Sounds cool, though will it cause problems?
Thank ya.
The low grumble noise is basically the engine bogging down. Power is lost. The car must be restarted to regain power and the noise goes away. If it's still confusing to understand, I can take a video.
Car starts fine. Upon startup, there is no pop pop pop from the exhaust, it's smooth. When the car is fully warmed up, it's only slightly choppier.
I'm getting a loud, loud belt whine. Sounds like I have an unmuffled kompressor. Sounds cool, though will it cause problems?
Thank ya.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
There is no doubt that the car is triggering limp mode when you throw a P0304. You must get that filter changed & maybe, because it is cheap we should change the plug wires on cylinder 4. I hate throwing parts at cars without proper diagnosis but the dealer does have an advantage because they can try things with lots of spares around. I'm suspicious of your CPS as well but it almost always causes hard starting which you don't have.
That loud belt whine is the tensioner pulley. If it really pisses you off change it. They all go sooner or later & have been improved.
That loud belt whine is the tensioner pulley. If it really pisses you off change it. They all go sooner or later & have been improved.
Last edited by Glyn M Ruck; Jul 22, 2010 at 06:10 PM.
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From: Orlando, FL
C240
There is no doubt that the car is triggering limp mode when you throw a P0304. You must get that filter changed & maybe, because it is cheap we should change the plug wires on cylinder 4. I hate throwing parts at cars without proper diagnosis but the dealer does have an advantage because they can try things with lots of spares around. I'm suspicious of your CPS as well but it almost always causes hard starting which you don't have.
That loud belt whine is the tensioner pulley. If it really pisses you off change it. They all go sooner or later & have been improved.
That loud belt whine is the tensioner pulley. If it really pisses you off change it. They all go sooner or later & have been improved.
That fuel filter does not seem like a fun job. Oh well, what must be done, must be done.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Sorry - did not realise you had done wires.
Yes it's safe to drive in limp mode. It's done to protect things.
The filter is not too bad to do with your capability. If that does not help we had better get that compression test done & maybe we are heading for an injector. We can do that but there is a chance it will be money wasted.
Yes it's safe to drive in limp mode. It's done to protect things.
The filter is not too bad to do with your capability. If that does not help we had better get that compression test done & maybe we are heading for an injector. We can do that but there is a chance it will be money wasted.
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From: Orlando, FL
C240
Sorry - did not realise you had done wires.
Yes it's safe to drive in limp mode. It's done to protect things.
The filter is not too bad to do with your capability. If that does not help we had better get that compression test done & maybe we are heading for an injector. We can do that but there is a chance it will be money wasted.
Yes it's safe to drive in limp mode. It's done to protect things.
The filter is not too bad to do with your capability. If that does not help we had better get that compression test done & maybe we are heading for an injector. We can do that but there is a chance it will be money wasted.
This is where I get confused. If I have poor fuel pressure, wouldn't all my injectors be causing misfires?
Or is the techron all part of the scheme? We're cleaning out injector four, while giving back maximum fuel pressure, which should cancel out the misfires, correct?
Lastly, if the injector is just faulty, we'll replace that.
Is that the correct road to take?
Thanks!
Edit: Also, can someone please explain limp mode to me a bit more? My car is terribly choppy and sounds absolutely horrid when limp mode kicks in. I guess that's regular?
