307 SW 1.6 petrol bad idol. - Peugeot Forums
Peugeot Forums - Peueot - Citroen Community
Home :: Peugeot Forums :: Rules :: Articles :: About Us :: Partner Vendors :: Advertise


Go Back   Peugeot Forums > Peugeot Models > 307
PeugeotForums.com is the premier Peugeot All Forum on the internet. Registered Users do not see the above ads.
Like Tree9Likes

Reply
 
LinkBack Thread Tools Display Modes
Old 23-08-18, 06:21 PM   #1
Member
 
Join Date: Aug 2018
Location: South Norfolk.
Posts: 73
Default 307 SW 1.6 petrol bad idol.

Hi there. My name is Adrian and my first post here. I am in need off some assistance with my wifes 2005 307 SW 1.6 16 valve petrol engine.

Basically it started to hold back from cold. No warning lights appeared and this would rectifiy itself after several seconds.
Well this fault has developed further last week into hard to start. Now when it does the car struggles to idol. On acceleration to try and keep engine running there is sever hesitation. Sounds like a really bad misfire and really lumpy idol. There are no water, or oil leaks. All very strange.

So I started going through the helpful posts on here and drawn a blank.

I replaced the MAP sensor. Pattern part.
I have removed and cleaned the throttle body.
I have fitted new spark plugs as they needed doing.

However the fault still persisted.
When I fitted the new pattern MAP sensor, because it seemed the most likely cause and it was also a cheap item to rule out, it did activate the engine fault light. This never appeared with old sensor oddly. I then gave up.

Unplugging the MAP sensor forced car into limp mode. But it drives much better like this. Just lacks power, but it least the engine does not seem to misfire so this ruled out Ignition coil pack.

I drove the car to my local garage to take a look and plug in more advance diagnostic than I have here. I have used this garage for years and they know I used to be a ex mechanic, so they are a genuine company I trust.
They put their diagnostic equipment on the car and found that their were a couple of codes. I can't remember them of the top of my head.
One was throttle actuator motor and the other fault was Inlet air temperature was reading -40f. The car runs very rich and I believe it is all down to the IAT sensor reading. The new MAP sensor was a aftermarket part and the garage said I need a genuine one which is now on order.

However, I am intrigued about testing the original sensor and new pattern sensor. So this is why I need help testing the MAP plug and the MAP sensor. I cannot find any info on pin configuration etc, or expected plug voltages, or grounds.
Can someone please help me with the MAP sensor expected plug voltages and the continuity tests to ecu as I need to check the loom. Also with ohms readings from the MAP sensor.

I did unplug the MAP sensor from the loom. None of the 4 pins on the wiring loom read as a chassis earth. May be ECU earthed somehow. Also very oddly when unplugged the other 3 connections in loom to sensor read 5V sitting on them. Now it might be correct, but I have no idea. So I may have a damaged wire somewhere or ECU fault. I really need to find out where the other end of the the MAP sensor loom is going? Any ideas.

Help would be much appreciated. Please excuse my spelling. Not great at best of times and on a mobile it is worse.

Last edited by adrianleigh; 23-08-18 at 10:18 PM.
adrianleigh is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 02-09-18, 03:59 PM   #2
Member
 
Join Date: Aug 2018
Location: South Norfolk.
Posts: 73
Default

I am still not there yet. I have received and fitted both a Bosch MAP sensor and Bosch throttle body. Both new genuine spares and I still get lumpy idol with no power. These are the fault codes in images I have taken from my diagnostic tool. I believe I have ruled out wiring as checked continuity from MAP plug to ECU harness plug. Although without a wiring diagram from MAP sensor wiring to ECU I am not 100% sure to the extent. I have numerous same coloured wires and not all of them show continuity. I have managed to trace 4 x wires with continuity though so assuming they don't go elsewhere. So I am assuming the ECU is knackered.
So I now need help with attached pictures and if it looks like the ECU, can it be reset? Or can someone recommend a agent where I can send it off too, to have the ECU and MAP circuit tested and repaired please. It has already cost me a bomb.

Thanks
Adrian.
Attached Thumbnails
20180902_130837_1535903163520.jpg   20180902_130821_1535903197529.jpg   20180902_130802_1535903216359.jpg   20180902_130754_1535903233824.jpg   20180902_101350_1535903264344.jpg  


Last edited by adrianleigh; 02-09-18 at 04:03 PM.
adrianleigh is offline   Reply With Quote Quick reply to this message
Old 02-09-18, 06:15 PM   #3
Senior Member
 
Join Date: Sep 2016
Location: Stoke on Trent
Posts: 1,792
Default

Doubt it is the ecu as you said the engine run OK in Limp so the ecu is working. Limp just restricts the rev range which on my 1.4hdi was 2850. I could still do 70 in top gear! Apart from idle what else is wrong?
Rereading your first post I reckon it is the sensor as in limp the ecu uses a list of standard figures to run the engine so if a sensor is duff the standard figure in the limp mode is correcting the duff signal and bingo all runs well!

Last edited by madbadandold; 02-09-18 at 06:19 PM.
madbadandold is offline   Reply With Quote Quick reply to this message
 
Old 02-09-18, 07:42 PM   #4
Member
 
Join Date: Aug 2018
Location: South Norfolk.
Posts: 73
Default

Thankyou madbadanold for your help and advise.

Well it is all rather odd.

The car struggles to idle. Often cuts out as though running on a few cylinders. Smells really rich as well. When you rev the accelerator with car stationary there is a major lag in response. The engine jumps around on the mounts in a bad way and tries to cut stall.

At first I thought it was a bad misfire. So I took the plugs out and checked them. Seemed fine, but they needed to be replaced so I fitted some new ones. Fault remained, but I wasn't surprised.
So then I was thinking maybe the coil pack, or valve/engine problem.
This was ruled out when I unplugged the MAP sensor and the car idled fine. Just lacked power because in limp mode, but does run on all four cylinders. Drives well all be it very lethargic under load, but with no map sensor in I a using the default settings.

So MAP sensor ordered and fitted. It was a pattern part and did not cure it either. So I put it into my local garage. They said there is a problem with the MAP sensor and to get another one. Which I did, but also they said the throttle body was also playing around with old codes. It did seem to fight your efforts to rev the engine, so tied up and I ordered that as well. Both genuine parts fitted and still the car cannot idol properly. Really lumpy when MAP sensor plugged in.

So I have now checked the voltage at MAP sensor and they look wrong. There are 4 wires to the MAP sensor and using the engine as the my digital meters earth reference, I read them all as 5 Volts, give or take a few milli Volts.
This I thought must have been a short in the loom somewhere. It does tie up with my readings from my fault code reader monitoring the MAP+IAT in one sensor. With engine running these do not change.
So I thought I would check some cold tests with regards continuity of wires to ECU and from MAP sensor. Easy at MAP sensor end, but not at ECU end. There are several same coloured wires appearing at the ECU end. I am assuming because of the way the ECU uses the MAP sensor these 4 wires only go to the ECU. It took a while earlier, but I found each wire from MAP sensor had continuity through to ECU and on only 4 wires. So I have no breaks in the wires. I then disconnected the plugs at MAP and ECU and tested for short circuits across the 4 wires. None of the wires have a shorted to each other.

I am assuming the ECU has a internal short somehow, but like you said, by unplugging the MAP sensor the ECU is using it's default programme. So I am wondering whether this is even possible.

I think my major problems is how can I have 5V on all four MAP sensor pins. Or is this what the ECU generates when in limp mode, but then why improve when I unplug it. I do not know which is the MAP Vcc supply pin, sensor earth, or signal back from IAT or MAP. So I am stuck in a loop re pins. I have looked online but not a lot to go on.

The car had a couple of times over past few weeks felt a bit laggy from cold like the old manual choke days. This seemed to rectify it self within minutes though.
It is my wife's childminding car. I had driven it fine the night before, as I went shopping in it. It was a rainy night though. So maybe a issue. This was 3 weeks ish ago now though.
My wife used the car as normal the following morning and the car broke down a few hours after being parked up for a hour whilst she collected some children.
She rang me saying the car wouldn't run. I asked her how was it driving to her destination. She said that it felt like it was holding her back from the very start, but no warning lights came on. I think this had already entered limp mode. When I got there the engine sounded like a bad misfire and would die immediately failing to run, it could hardly rev without major hesitation. There was no way it would drive. We got the car towed back home. It was here I found out that disconnecting the MAP sensor improved things dramatically. Every time I plug it in it struggles to idle.

So I am confused to say the least.

I also checked and cleaned the ECU's earth connector to the N/S inner chassis just in case I had a floating ECU earth, but this failed to improve things and reads fine, so is another item of the list.

I just keep going back to having 5Vs on all four MAP wires. Something really odd here I think and like my above image above there was no readings from the MAP sensor was I drove it around a little. It does seem better than when it originally broke down so I am wondering about water ingress but cannot see any near the ECU, or its connections.

So still scratching my head here.
adrianleigh is offline   Reply With Quote Quick reply to this message
Old 02-09-18, 08:49 PM   #5
Member
 
Join Date: Aug 2018
Location: South Norfolk.
Posts: 73
Default

I have one other odd thing I have just noticed this evening. When I turn the ignition on, I get a constant sort of whining whistle in the background. It is coming from the throttle body as though a motor is straining. This happens with the old one as well. If I unplug the connector to the throttle the noise stops. Oddly if I check the the MAP sensor voltage then I only get voltage on two of the pins. The centre ones. I really need a wiring diagram.
adrianleigh is offline   Reply With Quote Quick reply to this message
Old 03-09-18, 08:59 AM   #6
Member
 
Join Date: Aug 2018
Location: South Norfolk.
Posts: 73
Default

After having advise from madbadanold with regards the ECU, I did more research and stubbled on this very useful link to a techincal PDF on the ECU fitted to my car. Also has setup procedure re motorised throttle body + TPS and wiring diagram so very handy wiring loom wise:

OPERATING PRINCIPLE -
BOSCH ME7.4.4 / M7.4.4 AND EOBD.

After reading this info and trying to some cold voltage checks and hearing the low level scream of a throttle motor try to work, I have attempted to reset the Throttle body and Throttle position sensor. It is early days, but the car started this morning and I drove it around the block. I still have no MAP, or Temp sensor readings on my fault code reader, but this may be because it is not planet, or it may still be a issue. This morning the car was in it's learning mode so drove a bit hesitantly to start with, but improved. At least the cars idle seemed to improve. No fault code lights appeared on the dash, with exception anti pollution warning before reset. Not seen this warning before. I am hoping this will work now. I will keep you informed as early days, but I would google and check out the above PDF as very interesting. You'll have to copy and paste the heading and do a internet search this way, as I am a newbie it will not allow me to post the actual link. Syndey is in the title of the web page your after. This will help explain the procedure etc.
adrianleigh is offline   Reply With Quote Quick reply to this message
Old 03-09-18, 10:29 AM   #7
Senior Member
 
Join Date: Sep 2016
Location: Stoke on Trent
Posts: 1,792
Default

Great info and write ups although sometimes difficult due typing errors in text. Note that the word Sidney is in the title! There are a lot of pages and the info is marked for Citroen but no doubt it also covers the pugs.
I found it impossible to find info on the wiring to/from the ecu when chasing my limp mode saga. Peugeot don't use set wiring colour coding just whatever is at hand when built apparently! I sent my ecu away for checking and as they could not find fault all I had to pay for was the postage by the way. But apart from ensuring there is no obvious circuit damage on the boards I don't think these firms can carry out in depth checks of each circuit in the ECU.
Is the wiring diagram in the pdf any use for this defect?
madbadandold is offline   Reply With Quote Quick reply to this message
Old 03-09-18, 11:43 AM   #8
Member
 
Join Date: Aug 2018
Location: South Norfolk.
Posts: 73
Default

Yes with regards wiring loom pin information. It sort of tells you the basics. As you said though there seems to be no reference to coloured wires used.

Unfortunately my car developed the same fault codes again and has returned to bad idle. This time MIL light came on. Same fault codes re ECU and detecting high MAP sensor voltages.

Ref attached image.
Item 1312 is the MAP sensor wiring and item 1320 is the ECU.

So pin 4 of 1312 looks like the neutral ref connection and pin 2 the supply voltage to the sensor.

Pins 1 and 3 are the return signals to the ECU. Not sure which, but one of the connections will be manifold pressure and the other air temp.

PIN 1 is a return through some comparitor circuit and pin 3 a return through a variable resistor.

So I believe for my MAP sensor to have 5V on each of its 4 pins suggest either a shorted sensor (unlikely as tried 3 now), or a possible ECU fault as wiring goes no where else? There is a possible loss of earthing to the MAP sensor and why the voltages are high. I am not sure whether sensor earth is also chassis/battery earth.
I will continue to look at this. Should the checks come back okay, I will have to contact a company who can check the ECU's MAP sensor circuit.
Attached Thumbnails
20180903_122949_1535974262669.jpg  

Last edited by adrianleigh; 03-09-18 at 11:50 AM. Reason: spelling
adrianleigh is offline   Reply With Quote Quick reply to this message
Old 03-09-18, 04:29 PM   #9
Member
 
Join Date: Aug 2018
Location: South Norfolk.
Posts: 73
Default

sidney.pro.br/ecu.pdf

Above is the site address I used for the manual.
It has www. at the beginning if this helps. Like I posted earlier, I am not permitted to post the link due to being new on here. It says it that is a unsecured site, but I have used it with no problem.

My car update.

What I have found by using diagram in above link.

Firstly, locate the outer ECU connector under bonnet, nearest to the wing (passenger side). C2- and C3+ are the power supply and return pins that come from the ECU to the MAP sensor. Going by the drawing you should have 5V across it those pins when ignition is on, or engine running. In my case I had no 5V across these pins.

If I use my multi meter to check the MAP sensor supply voltage pin 2, whilst using my meter on chassis/battery ground I do get 5V. Odd, but it proved that 5V supply is there. So all seemingly looks okay. Well looks can be deceiving, don't be fooled like me. It does not check the neutral return circuit of this sensor to ECU.

Make sure you measure 5V across pins 2 and 4 at the MAP sensor first (+ & -). If you have voltage across here, you will probably just need of a new MAP sensor.

If no voltage like in my case, then secondly proceed to check for MAP sensor supply at the outer ECU connector nearest to the near side wing.
Pins C2 and C3 are what you need to find. You should get 5V across here. (Do not use chassis earth). Easier to use a couple of needles for this and gently probe into outer sheath of the corresponding cables coming from C2 and C3. Be careful not to short anything out. Access to the ECU plug pins are almost impossible. This is basically checking the same MAP sensor supply wires, but directly out of ECU. If you have voltage here and not at the MAP sensor, then check your loom for open circuits between ECU and MAP sensor using continuity tests. Obviously disconnect the battery first. PLEASE FOLLOW THE INSTRUCTIONS for disconnecting the battery correctly elsewhere on this site to avoid ECU / BSI corruption.

In my case I still had no voltage across C2 and C3 either at the ECU end. This indicated a problem either at the ECU connector, or the ECU itself. Unplugging the connector and checking continuity tests found no faults with the connector on mine, so I have no choice other to assume the ECU is faulty.

My conclusion.
The MAP sensor is not being energised properly because of there being no neutral return circuit with the ECU itself (floating earth). I did think about shorting the neutral wire to chassis earth, but as this neutral comes from the ECU itself, I wasn't sure if this would be a true earth, hence why you have to read across the wires and not from earth. I didn't what to damage things further than they already are so just have to bite the bullet. I did check continuity with the neutral MAP sensor wire to chassis/battery earth and it did not show as having continuity. So not surprised. However, I am not sure if the MAP sensor neutral uses a specific earth for that sensor.

I have sent of ECU for repair. Hopefully this will be sorted. I will update you all when I find out myself.
Attached Thumbnails
ecu-wiring.jpg  

Last edited by adrianleigh; 03-09-18 at 05:06 PM.
adrianleigh is offline   Reply With Quote Quick reply to this message
Old 03-09-18, 05:51 PM   #10
Senior Member
 
Join Date: Sep 2016
Location: Stoke on Trent
Posts: 1,792
Default

Brilliant thread. Cannot wait to see the results of the ECU circuitry.
madbadandold is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Peugeot Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in


Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT. The time now is 07:13 AM.



Powered by vBulletin® Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.