NEED HELP DESPERATELY. 2003 Chrysler 2.5

[bandbauto]

I have a 2000 Chrysler Sebring 2.5 v-6 that has a P0300 dtc and pending dtc's p0301-0306. The vehicle was at another shop and had a crank sensor and distrubitor put in, it was towed in for a no start. The customer said the vehicle had no problems previous to these repairs being done. I have replaced the crank sensor and distributor and still have the same problem. While driving down the road only (not in the bay in park or loading in the bay) will the engine count misfires but I cannot feel any misfires actually happening. The fuel pressure is 51-52 (spec. is 49) the cylinder compression is 205-185 highest to lowest. I can watch the crank sensor with the LAB SCOPE and the sensor reading is erratic to me, I will try to attatch acopy of the crank sensor data. Any help will be greatly apprieciated or even a discussion as I have done a lot of other checks also to type. I also have noticed that it seems to only start counting misfires at approx. 21-2200 prm or higher.

[sdlindsey]

Hi,

Try downloading the Shopstream Connect w/ Ask-A-Tech Live software, and then opening a help request.

As a bit of help: Try scoping the sensor at a lower time base, then zooming out. You may be seeing scope aliasing. Also, I would advise CMP and CKP on the same screen. Try a 50ms time base, capture a bit, then pause the output and zoom out to see the whole engine cycle.

How are the motor mounts? Transmission mounts? Flywheel/flexplate? How is the balancer?

[bandbauto]

The Mounts were previously replaced and the flywheel looks ok but I am only looking through the sensor hole at the tonewheel. The 2 mounts for the center of the motor for and aft have been done and the other 2 look and feel ok- no excessive movement. Just curious but what will the live software and help request do for me?? Will thatmean that the datacan be viewed live by anyone or that it will ben like a chat room? I haven't heard of this or know anyone who has used it. Thanks for the reply.

[Earl Davis]

I have a 2003 Chrysler Sebring 2.5 v-6 that has a P0300 dtc and pending dtc's p0301-0306. The vehicle was at another shop and had a crank sensor and distrubitor put in, it was towed in for a no start. The customer said the vehicle had no problems previous to these repairs being done. I have replaced the crank sensor and distributor and still have the same problem. While driving down the road only (not in the bay in park or loading in the bay) will the engine count misfires but I cannot feel any misfires actually happening. The fuel pressure is 51-52 (spec. is 49) the cylinder compression is 205-185 highest to lowest. I can watch the crank sensor with the LAB SCOPE and the sensor reading is erratic to me, I will try to attatch acopy of the crank sensor data. Any help will be greatly apprieciated or even a discussion as I have done a lot of other checks also to type. I also have noticed that it seems to only start counting misfires at approx. 21-2200 prm or higher.

I agree with the lower time base recommendation. I would also capture the distributor sensor and compare to the crank. If you installed and aftermarket distributor it is possible it has the same problem as the one you replaced. I have seen several after market dist. replaced on these before getting a good one. Also have you looked at the secondary firing events? What about plugs and wires? Does the misfire occur only under load or no load? If the ckp waveform was captured during misfire event it will not look normal because the crank shaft is speeding up and slowing down while misfire is occurring.

Are you sure of the year on this one? I thought Chrysler stopped using the 2.5 before 2003.

Earl

[Skip]

Just curious but what will the live software and help request do for me?? Will thatmean that the datacan be viewed live by anyone or that it will ben like a chat room? I haven't heard of this or know anyone who has used it. Thanks for the reply.[/QUOTE]

Shopstream Connect is for specific technical questions such as yours. SnapOn is trying to keep this forum for scanner/scope issues and the other for tech questions involving repairs.

[40twist]

Check for a cracked flywheel up around the bolts , look for rust dust.

[eddiesverus]

Have you also checked the crankshaft end play? I once had a GM vehicle with a similar problem and found the crank shaft had excessive end play causing the crank to move out of the CKP range and set misfire DTC's. the scope pattern was erratic as yours. So just an other thought good luck.

[dbarnes5654]

I agree with 40twist. Chrysler had a problem with cracked flywheels. Last one I did had no rust dust evident, had to pull trans and flexplate to see it but it was most deffinetly cracked.

[David06wing]

repaired with oe part

To everyone who thoughtfully replied to the thread posted thank you. In the end the problrem is that the crank sensor pattern is "normal" beleive it or not. I compared it to another vehicle that came in with no problems but it has the same pattern as my problem vehicle. What I ended up doing is replaced the crank sensor with a mopar part and then the problem was solved. No more misfires at all being counted even though the pattern still looks the same. Just thought you guys might want to be aware of the horrible pattern. David from B&B AUTO

[davesautoserviceinc]

Is this a Manual Transmission?

If so the clutch may be causing the miss counter.

[Rich Shepherd]

To everyone who thoughtfully replied to the thread posted thank you. In the end the problrem is that the crank sensor pattern is "normal" beleive it or not. I compared it to another vehicle that came in with no problems but it has the same pattern as my problem vehicle. What I ended up doing is replaced the crank sensor with a mopar part and then the problem was solved. No more misfires at all being counted even though the pattern still looks the same. Just thought you guys might want to be aware of the horrible pattern. David from B&B AUTO

Hi David,
The scope is capable of displaying good patterns for this sensor.
The reason the crank sensor pattern appeared to be dropping out is due to the time sweep selected. At the 2 Second sweep, this sensors transitions may fall between the scopes sample points and therefore appear to drop out.
There are 2 things to do when faced with this situation:
1. When viewing this particular sensor waveform on sweeps longer than about 100 ms, you should turn on Peak Detect. The selection is on the channel menu for each channel and when "checked" On will display a small icon (looks like 2 mountain peaks) at the top of the scope screen for the channnel it is selected. This mode handles sampling differently and will capture all of the sensor transitions. Please note that at sweeps of approximately 500 ms and above, the waveform for this sensor may start to look like a solid curtain because the number of sensor transitions will become equal to or greater than the number of display points across the scope screen. The exact point that happens will be based on engine RPM and the sweep selected.
2. Use a sweep of 100 ms or less. You may not be able to see the waveform for the full rotation of the crank on one screen at the faster sweeps, but you will get a waveform that does not drop out. To see the waveform for the full rotation, just freeze and then review it across a couple screens.
The Zoom Out feature may be helpful when reviewing a waveform such as this.

The best way to see what the Peak Detect feature will do for you in a case like this is to try it both On and Off thru a range of sweeps from 100 ms to 2S. There are times when you will want to use it and other times when you will not want to use it. It is an important feature that you should take some time to experiment with and learn what it can do for you.

[joenash]

I was talking to another tech and he was saying that some vechiles have what they call know good failures, ohm the sensor out scope it and it looks okay but it is just bad, i know it kind of sucks how the hell are you supposed to tell what is wrong with the car?????????????????

[mannymejias]

check EGR

did you tried EGR VALVE something similar happent to me...good luck

I have a 2000 Chrysler Sebring 2.5 v-6 that has a P0300 dtc and pending dtc's p0301-0306. The vehicle was at another shop and had a crank sensor and distrubitor put in, it was towed in for a no start. The customer said the vehicle had no problems previous to these repairs being done. I have replaced the crank sensor and distributor and still have the same problem. While driving down the road only (not in the bay in park or loading in the bay) will the engine count misfires but I cannot feel any misfires actually happening. The fuel pressure is 51-52 (spec. is 49) the cylinder compression is 205-185 highest to lowest. I can watch the crank sensor with the LAB SCOPE and the sensor reading is erratic to me, I will try to attatch acopy of the crank sensor data. Any help will be greatly apprieciated or even a discussion as I have done a lot of other checks also to type. I also have noticed that it seems to only start counting misfires at approx. 21-2200 prm or higher.