No Power after 3500rpm
#11
RE: I would be 95% this is your problem
Hi have some new news, first let me stat by say thanks for all the tips and insight. I pulled the upstream o2 sensor and ran the car like that, yes then it set the check engine light. After warm up when it normaly would lose power at 3500rpm it ran fine. Then I left it cool down and started it up (cleared the o2 code first) then went for a drive 50 miles, city, highway and ran fine, so it seems like it might be the converter b/c now the exhaust can get out infront of it. I will take it out one more time tomorrow to make sure, but I think you found the problem. A couple of things still bother me, why would it not set a check engine light if the reading down stream was clogged, why would my exhaust not smell funny and why would it not run hot? If this is my problem any ideas where to get a cat other that the dealer? Thanks
#12
RE: No Power after 3500rpm
well u got us both. he is right my test failed but it still could be his. although u would it let u get to 3500 then quit? what sensor input is it that ur getting to choke ur fuel and it always seems to be under load.
from what i gather :
cold runs fine for a minute till warm up
warm only till 3500 then falls on its face
gear selction still works same as d with same symptoms
car idles well and in more than one gear the peak is 3500? b4 blaaaahhhh n it pops or makes a popping sound.
well id work from the begininning.
no check engine light at all.
so it cant be an input from a sensor although its acting like a sensor failure.
id venture two things:
a sensor has failed by getting stuck in a variable i.e. constantly open which is great for cold runs and start up since input doesnt matter or constantly closed same deal.
or
its mechanical-which im not so sure of on handling. honestly id walk thru the basics narrow the problem.
do a compression test u can rent the tool for free at advance or pepboys return tool gives u all ur money back. check each cylinder.
check each spark plug wie or stem for spark use paper clip method.
then check ur fuel rail or injectors for fuel dump dont use foam cups it likes to be eaten by gas haha.
this will tell u i the basics are functioning. if they all are ur work isnt in vane.u just narrowed it down to a sensor. because on starup all these things lets say function properly its warm up runs closed loop taking input from various sensors like i said before. and now u know its not throwing a check engine light because the sensor is faulty but faulty within specs which is causing u driveability issues but not engine damage. man i wish i could see this car hahah see what pj and silver say matbe they can narrow my idea down. keep us updated.
from what i gather :
cold runs fine for a minute till warm up
warm only till 3500 then falls on its face
gear selction still works same as d with same symptoms
car idles well and in more than one gear the peak is 3500? b4 blaaaahhhh n it pops or makes a popping sound.
well id work from the begininning.
no check engine light at all.
so it cant be an input from a sensor although its acting like a sensor failure.
id venture two things:
a sensor has failed by getting stuck in a variable i.e. constantly open which is great for cold runs and start up since input doesnt matter or constantly closed same deal.
or
its mechanical-which im not so sure of on handling. honestly id walk thru the basics narrow the problem.
do a compression test u can rent the tool for free at advance or pepboys return tool gives u all ur money back. check each cylinder.
check each spark plug wie or stem for spark use paper clip method.
then check ur fuel rail or injectors for fuel dump dont use foam cups it likes to be eaten by gas haha.
this will tell u i the basics are functioning. if they all are ur work isnt in vane.u just narrowed it down to a sensor. because on starup all these things lets say function properly its warm up runs closed loop taking input from various sensors like i said before. and now u know its not throwing a check engine light because the sensor is faulty but faulty within specs which is causing u driveability issues but not engine damage. man i wish i could see this car hahah see what pj and silver say matbe they can narrow my idea down. keep us updated.
#13
RE: No Power after 3500rpm
Hey guy's I have some good news, it turns out it was a coil over. After driving for awhile it would heat up and under heavy load fire weak. There was a small crack in the side of the coil causing the problem. I put a new coil on and it runs great at all rpms all temp ranges. Thanks for all the help and advice I know its hard to diagnosis a car without seeing it, but your tips got me looking outside the box. Thanks again hope I can help you some day.
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