As the title states, vehicle has been an absolute dream since she came back to life but I have been noticing almost a pulsating vibration accompanied by a low idle when in gear. Once the car is in neutral or park vibration is not present. Idle in gear is just below 500 rpm, I haven’t had the chance to measure gap between oil pan and crossmember yet, but I did dry to lift the engine slightly with a floor Jack and wood to see if it lifted up, and it didn’t. I did pull a code for Neutral Safety Switch a while back when check engine and ASR had come on.. what’s the next step?
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1995 E420 with low idle and vibration
- Thread starter mnessari
- Start date
Two things:
1) You need to confirm whether your car has had its upper wiring harness replaced, or not. If it has not been replaced (use the HOW-TO on checking the tag for age/manufacture date), you need to replace it.
2) You need to use a blink code reader to remove all of the codes from all of the modules (not just the Diagnostic Module, which controls the CHECK ENGINE light); then drive the car 50-100 miles. Then check the codes again, and report back with what you find. This will help the forum diagnose your issue.
1) You need to confirm whether your car has had its upper wiring harness replaced, or not. If it has not been replaced (use the HOW-TO on checking the tag for age/manufacture date), you need to replace it.
2) You need to use a blink code reader to remove all of the codes from all of the modules (not just the Diagnostic Module, which controls the CHECK ENGINE light); then drive the car 50-100 miles. Then check the codes again, and report back with what you find. This will help the forum diagnose your issue.
In addition to what Gerry posted above... normal idle speed at full operating temp (80C+) is 500-550rpm in gear, and 650rpm in P/N.
Clear all codes and see what codes come back. And you MUST measure the engine mounts. If they are not recent, it is very very likely they are collapsed.
Clear all codes and see what codes come back. And you MUST measure the engine mounts. If they are not recent, it is very very likely they are collapsed.
Thank you so much for the insight. I did confirm harness was updated with a Delphi harness in 2012. I pulled codes using a blink reader and they are as follows:
Pin 6: 30 blinks (ABS ETS ASR ESP)
Pin 7: 2 blink and 6 blinks (EA ISC CC)
Pin 14: On Solid (Lambda On/Off)
Pin 16: On Solid (HEAT TA/C)
Pin 19: 6 blinks and 26 blinks (Diag Module)
Pin 30: 8 Blinks (Airbag)
As for the idle, when warmed up I’m at about 480-490 in gear but normal in P/N.
Pin 6: 30 blinks (ABS ETS ASR ESP)
Pin 7: 2 blink and 6 blinks (EA ISC CC)
Pin 14: On Solid (Lambda On/Off)
Pin 16: On Solid (HEAT TA/C)
Pin 19: 6 blinks and 26 blinks (Diag Module)
Pin 30: 8 Blinks (Airbag)
As for the idle, when warmed up I’m at about 480-490 in gear but normal in P/N.
That is correct! If I’m reading correct,
PIN 6
code 30 for CAN data bus to EA/CC/ISC control module (N4/1), interrupted,
PIN 7
code 2 is EA/CC/ISC control module (N4/1)
code 6 for:
Safety contact switch (M16/1s1)
Stop lamp switch (S9/1)
Safety contact switch (M16/1s1)
Criuse control switch (S40) OFF
PIN 19
Code 6 idle speed control inoperative (test electronic accelerator)
Code 26 Upshift delay switchover valve, open/short circuit (test Test LH-SFI, section 3.1)
Correct me if I’m wrong, but NSS and something that may have to do with idle speed?
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Pin 6 code 30 is a useless generic code that appears every time limp mode is triggered. Ignore this.
The codes on pin 7 are what will likely fix the problem.
Pin 19 is for the DM which is just a watchdog, it monitors CAN data and triggers the CEL when there is an emissions-related fault. And ONLY for emissions-related faults. Fix the problem and the pin 19 codes (and CEL) will go away.
The codes on pin 7 are what will likely fix the problem.
Pin 19 is for the DM which is just a watchdog, it monitors CAN data and triggers the CEL when there is an emissions-related fault. And ONLY for emissions-related faults. Fix the problem and the pin 19 codes (and CEL) will go away.
OK got it, thank you. I have no check engine light illuminated. Correct me if I am wrong but first step maybe to replace Neutral Safety Switch, then the Module if all else fails?
The NSS can cause limp mode (and ASR light on) but should not cause idle speed problems.
Is the ETA original? If not, what is the date code, or date of rebuild?
Also, is the main issue here strictly vibration at idle, no ASR light, no limp mode? Vibration is very, very likely to be engine mounts.
Those are accumulated codes. They can mean nothing, or a lot, but are going to be old and somewhat irrelevant to your problem.
As I said in my earlier post, erase all of them and drive the car again for 50-100 miles, and check what comes back. THOSE will be fresh and relevant codes, that you can concentrate on.
You definitely described limp-home mode, and as the @gsxr said there are a number of things that can cause it. Don't throw any parts at anything until you have a fresh set of codes to deal with.
And as said, please check the date on the outside of your ETA. There's more info on how to do that on the forum.
As I said in my earlier post, erase all of them and drive the car again for 50-100 miles, and check what comes back. THOSE will be fresh and relevant codes, that you can concentrate on.
You definitely described limp-home mode, and as the @gsxr said there are a number of things that can cause it. Don't throw any parts at anything until you have a fresh set of codes to deal with.
And as said, please check the date on the outside of your ETA. There's more info on how to do that on the forum.
Right at this moment no. I did clear the codes and put about 100 miles since. Before the clearing of the codes I had a code 2 and code 6 on pin 7
@mnessari what ended being your problem??
I have a similar condition at cold starts while idling in park. I checked my codes and I also have code 30 on pin 6! Also got code 14 on pin 7, code 6 on pin 8 (that’s been always there).
I am suspicious that my EA/CC/ISC control module is the main problem, because I do NOT have limp mode nor ABS/ASR lights. Or it’s that throttle switch that is faulty. What do you all think? Would a bad/faulty throttle position switch (S29/3) drop the rpms below about 500!?
I’ve had this problem ever since I bought the car two years ago and never had code 14 on pin 8.
Last time I had cleared all codes I didn’t have anything related.
I have a similar condition at cold starts while idling in park. I checked my codes and I also have code 30 on pin 6! Also got code 14 on pin 7, code 6 on pin 8 (that’s been always there).
I am suspicious that my EA/CC/ISC control module is the main problem, because I do NOT have limp mode nor ABS/ASR lights. Or it’s that throttle switch that is faulty. What do you all think? Would a bad/faulty throttle position switch (S29/3) drop the rpms below about 500!?
I’ve had this problem ever since I bought the car two years ago and never had code 14 on pin 8.
Last time I had cleared all codes I didn’t have anything related.
See posts #3, #5 and #7 above. 500rpm is normal in gear.I have a similar condition at cold starts while idling in park. I checked my codes and I also have code 30 on pin 6! Also got code 14 on pin 7, code 6 on pin 8 (that’s been always there).
I am suspicious that my EA/CC/ISC control module is the main problem, because I do NOT have limp mode nor ABS/ASR lights. Or it’s that throttle switch that is faulty. What do you all think? Would a bad/faulty throttle position switch (S29/3) drop the rpms below about 500!?
I’ve had this problem ever since I bought the car two years ago and never had code 14 on pin 8.
E-GAS code #14 is for S29/3, you need to fix that first. It is very unlikely your E-GAS module is bad.
I have 500rpm in park at cold starts. I would also suspect my throttle position switch to be on it’s way out. I have low MPGs and slight rough idle in park! Thanks. I’ll look for a replacement.See posts #3, #5 and #7 above. 500rpm is normal in gear.
E-GAS code #14 is for S29/3, you need to fix that first. It is very unlikely your E-GAS module is bad.
Ah, ok, 500rpm in Park isn't normal. I'm not sure if S29/3 will affect this or not. However, you can get a fault for S29/3 if the throttle linkage is not adjusted properly - check that first, before replacing the switch. This is much easier with a digital scanner that shows live data from the E-GAS module.
Low MPG would be completely separate, but make sure the odometer isn't intermittent. For the rough idle, how old are engine mounts, and have they been tested (measured) to verify they aren't collapsed?
I don't have a digital scanner to be able to check for the live data, but will ask them to check when I go in for service at my MB shop.
As for the rough idle, my odometer is perfect and not intermittent. My car might also have a combination of problems, maybe a small vacuum leak could be the result of low rpms at idle, that I never got around to dig into since I bought her. The engine mounts are original with only 101K mileage on the car. They will be next on my to-do list.
I wish I had an update! I been driving my old girl as is, some days it idles perfectly in gear when there is a load and and some days I feel the pulsating vibration while barely holding on the the 500 rpm mark while in gear, but idle in park is smooth as can be!@mnessari what ended being your problem??
I have a similar condition at cold starts while idling in park. I checked my codes and I also have code 30 on pin 6! Also got code 14 on pin 7, code 6 on pin 8 (that’s been always there).
I am suspicious that my EA/CC/ISC control module is the main problem, because I do NOT have limp mode nor ABS/ASR lights. Or it’s that throttle switch that is faulty. What do you all think? Would a bad/faulty throttle position switch (S29/3) drop the rpms below about 500!?
I’ve had this problem ever since I bought the car two years ago and never had code 14 on pin 8.
Last time I had cleared all codes I didn’t have anything related.
Im back!!!!!
Ok so we went a few months of enjoying the car and I’m still enjoying but ASR made a comeback. I still haven’t gotten to replace to rebuild eta, my idle is still kinda low in gear but now when warm, my idle in park is about 500rpm. The asr light comes on when I punch it and car downshifts. As soon as I turn it off the light is gone and drives great under calm driving conditions. I pulled codes with the blink reader and I got the following:
PIN 4: 1
PIN 6: 30
PIN 7: 2/6
PIN 19: 6
I also got a pic of my eta and to me looks like 94/M03 but with updated wiring?
Should I replace NSS? Or ETA? Lower harness brittle? ASR switch? Or all of the above?
Ok so we went a few months of enjoying the car and I’m still enjoying but ASR made a comeback. I still haven’t gotten to replace to rebuild eta, my idle is still kinda low in gear but now when warm, my idle in park is about 500rpm. The asr light comes on when I punch it and car downshifts. As soon as I turn it off the light is gone and drives great under calm driving conditions. I pulled codes with the blink reader and I got the following:
PIN 4: 1
PIN 6: 30
PIN 7: 2/6
PIN 19: 6
I also got a pic of my eta and to me looks like 94/M03 but with updated wiring?
Should I replace NSS? Or ETA? Lower harness brittle? ASR switch? Or all of the above?
Bump!
Last edited by a moderator:
Get that ETA refurbished.
www.500eboard.co
FYI - Electronic Throttle Actuator (ETA) Rebuild | M119 Engine
If you need to get your ETA rebuilt (and if you have not previously done so, or have not installed a newer replacement ETA, you DO need to get it rebuilt), an excellent resource to do this is Don Roden, owner of RFC Electronics in Hillsboro, Alabama. Don is hyper-knowledgable about ETAs, is a...
First verify NSS adjustment. If adjusted correctly, next is to replace (then adjust the new NSS correctly). Ideally you would view live data to see the gear position reported to the E-GAS module in each shift gate position, but I'm assuming you don't have a digital scanner / SDS to check. Getting the correct gear position indication to he E-GAS should cure the 500rpm idle in Park/Neutral (should be 650rpm at operating temp).
If the issues persist with the new NSS, then an ETA rebuild is next, via Don Roden at the link Gerry posted above.
Lower harness has nothing to do with these issues, the lower harness only affects the starter, alternator, and oil pressure/level sensors.
There is no "ASR switch".
As always, you guys on this forum have come through! I’ve been in multiple forums, from JDM, to Muscle to this forum and this forum is by far the most powerful thanks to all the knowledge you guys have, thank you. I was confusing S29/3 as an asr switch instead of closed throttle position switch. My bad lol. I just ran the blinks again I also got 2/6/14 on pin 7 and the common denominator is s29/3 in all codes. I may replace that if not I’ll ship out eta for a rebuldFirst verify NSS adjustment. If adjusted correctly, next is to replace (then adjust the new NSS correctly). Ideally you would view live data to see the gear position reported to the E-GAS module in each shift gate position, but Im assuming you dont have a digital scanner / SDS to check. Getting the correct gear position indication to he E-GAS should cure the 500rpm idle in Park/Neutral (should be 650rpm at operating temp).
If the issues persist with the new NSS, then an ETA rebuild is next, via Don Roden at the link Gerry posted above.
Lower harness has nothing to do with these issues, the lower harness only affects the starter, alternator, and oil pressure/level sensors.
There is no ASR switch.
Note that faults pointing to S29/3 doesn't always mean the switch is bad. Much more likely to be a mis-adjusted throttle cable. See link below, read the blue text at the top of the first post:
Replace Idle Switch S29/3 at accelerator pedal | Electrical, CAN and Wiring
ADMIN EDIT: If your car has an error code for switch S29/3... first, make sure the throttle linkage is adjusted correctly, per FSM procedure! If a replacement ETA has been installed, the throttle linkage may require adjustment. If it is not adjusted perfectly, it can cause an error code on...
www.500eboard.co
So it looks like I have a connecting bar rather than a connecting rod. I still measured 134mm, I wasn’t far off at all but I cleared codes again on pin 7 to see what happens. Thanks again!
That bar in your photo will adjust the transmission control pressure (Bowden) cable. Move it a few mm in either direction and your shift RPM changes.
The throttle cable adjustment is made by turning the knurled collar on the driver side:
Make sure there is some play at the very end by the spring. The cable should not be pulling on the lever at all, in the idle position.
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