After replacing timing belt one cylinder stops working/error codes P1336 and P1337

These are crankshaft sensor wiring issues please have them check the sensor wiring connector of corrosion or damage. Please let us know what you find. We are interested to see what it is.

Cheers, Ken

Yeah, that sounds so close to the solution. I hope it it what it is. I am an electronics engineer. I will check it myself. The mechanics from Chile sucks. One more thing I recently changed the crankshaft sensor, and now I was able to go to more rpm's with no issue, but still it has the same problem after 3,500 rpm's I used to lose a cylinder.

Tomorrow I will check the wiring and let you know. Thank for helping me out. I have been having these issue for a year. It is one year of frustration. It sucks. I hope best for tomorrow. Figure crossed.

Thank you again!

Sounds good, try to test the continuity between the sensor and the PCM. I know you are an electronics engineer by this guide might help.

https://www.2carpros.com/articles/how-to-check-wiring

Please run down this guide and report back.

Cheers, Ken

Hi Ken,

You have been really helpful in every step. I read all the instructions and followed it. The diagnosis is as below

1) I checked the wiring right till the connector that goes to the ECU.
2) Even the wiring was okay. I replaced it with a new one and now it has new wiring.
3) I checked the output voltage of the sensor which is of course an AC signal and it reaches till 5 volts or above corresponding to the acceleration. This voltage reached until the connector it the ecu without any issue.
4) I tested the car, still it has absolutely the same issue as before. One of the cylinder of the engine stops suddenly as soon as I go above 2,500 RPM's. Below 2,500 RPM's I have no problems whatsoever.
5) So when the cylinders stop the engine starts shaking, still running, but loosing the power.
6) After that to get it normal, I have to turn off the car completely and restart it , and the everything works just fine.
7) Again if I go above 2,500 rpm's, one cylinder stops.
8) When I am on a highway and my car is on the down steep, of course due to gravitational force it goes by itself, and in that scenario if I do not accelerate and the car goes itself above 2,500 RPM's then at that time no cylinders misfires/stops.
9) At the same time when I am on a down steep and the car is above 2,500 RPM's by itself and if I accelerate little bit then one cylinder stops.
10) Since I have been having this issue since one year and no mechanic has been able to fix it, I have started my own diagnosis. So I have learnt a trick to avoid this. What I do is I just accelerate but not in an constant manner, so to say like ( imagine my foot is on the pedal) zuuuuuuuu..........(one second break) zuuuuuuuu....(one second break).......zuuuuuu........and so on. In this way the car does not stop but my foot pains so much after an hour. Of course that is not the solution.

I do not know Ken. This is all I could give you the information. I am frustrated like crazy.


Please please please help me.

Thank you!

Regards,

All of this started after the job correct? Lets check the wiring harness grounds it sounds like one of them is loose or corroded. Follow the harness to see where it grounds to the engine near the front where they were working. Let me know, you might need to get under the car to see everything.

Hi Ken,

You mean to say I should follow all the grounds that car has. Or only one that has relation with crankshaft sensor. I have a question:

1) Do you think it can also be because of the ECU?
2) Do you think it can be the Cambelt ( that also I changed right before this all started)?

If you above question's answer are no then I will stop worrying about Cambelt and ECU.

Thanks Again Ken,

Please walk me out of this messy problem.

No problem, if all the problems started when the belt was changed the belt is where I would look first. If the shop that did the work says it is okay take it to a different shop. Make sure the marks are lined up.

Hi Ken. I am replying quite late, but did the revision of timing belt with the other mechanic and according to him the timing belt was not installed properly. So he did install it properly and now I still have the same issue. After 2,500 rpm, the cylinder stops working. I do not know what to do.

Can you please help me?

Please remove the valve cover and look for a broken valve spring using a flash light. This guide can help:

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Please run down this guide and report back.

Cheers, Ken

Sure Ken, I will do it. As I have mentioned before, that this problem when the cylinder stops working after 2,500 rpm's, goes back to work normally after I turn off the engine completely and restart the car. So do you still think it can be the spring in the valve? Please do not think that I am questioning you. I just have this minor doubt. Because I think that if the spring is compromised then the problem should not be associated with restarting the engine. Please help.

Cheers,

Yep, that would not be a valve spring sounds more like the PCM is going bad since it can be reset.

Yes I would say the same. What would say about the multi-functional injection relay? Do you think it can be the culprit. Today I will put the signal from crankshaft sensor on oscilloscope to study it.

Regards

I do not think it is the relay because it would affect all of them. It sounds like an injector driver is going out inside the PCM.

Do you know how to to identify an injection driver? What is the name of the IC. I can replace it. I am an electronics engineer. Should be okay for me.

Coming in late in the game here. What were the results of your testing with the scope? Can you post a picture or video of the scope trace while revving the engine up to 2500+? Also, we would not have the schematics of the ECU to be able to identify the driver transistors for the injectors in the ECU. And also can you confirm that you are still receiving those same codes (P1336 and P1337). The next step in my mind would be to probe each of the injector signals coming from the ECU. If you have a four channel scope you could do them all at once. I would like to see a scope trace of that as well if you are able.
Jon

Hello there, yes I can send you the video. We have tested with a multi-meter at the output of each injector so what happens is after 2,500 rpm's, one of the injectors gets 12 volts on both terminal making potential difference of 0 volts and hence the injector stops working. All is see that the culprit is the ECU.

Also just thinking here, You mentioned that you have already replaced the injectors so I am pretty confident that the injectors themselves are in good shape. I would feel better if we could ring out the harness that connects them to the ECU.

These are all Low-Side Drivers so, on the two pin connector with Key On Engine Off, you should see 12 volts on one of the pins and 0 on the other. The ECU has the power transistors that will sink the injector current to ground. Check that you have a solid 12 volts to one pin on each of the injector connectors and then test that each shows infinite resistance to ground on the other pin. Let us know what you find.

A scope trace would be really nice to see for this and it sounds like you have the capability to do so! That is exciting! The waveform you are looking for is a bit of an inverted square wave where you start at system voltage 12vdc nominal, then when the driver reaches saturation the voltage will drop as it sinks to ground. Then, when the driver is turned off, there will be a spike as the pintle in the fuel injector closes. This can vary depending on the impedance of the injector coils, and the type of clamping in the circuit. The width of the "injector-on" time (or duty-cycle) will change based on RPM and engine load. This is why I think this would be an excellent diagnostic tool for your problem.

Hopefully we can get to the bottom of this quickly for you.

Ciao
Jon

Okay, the sensor waveform looks just fine. That is what I would expect to see. See my last post =)

The waveform I have sent is from the output of crankshaft sensor. Which looks okay and as I accelerate, I see that the frequency increases means to day that the wave form has the same amplitude but the waveform squises.( obviously) . If you take a look at the video I do see some interference in the waveform, I was expecting it to be pure. Anyways, the wire harness to the injector looks okay. And I will put the oscilloscope on the output of the injectors as you asked me to do. Even though the result that we got from multi-meter was that the injector gets 12 volts on both terminal and hence it stops working, which looks like the ECU injection drive Bosch 30566 is the one which can make this happen. What do you say?

Yes, I did see the interference on the scope trace. By the way, I have a Rigol scope too, 50 mhz 2 channel. Love it! Saving up for a nice 1Ghz Mixed Domain (I do a lot of EMC work). I would attribute the interference to just having inserted a nice Dipole antenna in the circuit! Nothing to worry about there. And yes you would expect the frequency to change with engine RPM so all looked good there.

Are you considering replacing the chip yourself on the MCU? I cannot find a datasheet on the 30566 to look at much less the schematics of the ECU but you are a brave soul. I am not a fan of working on SMD's my eyes are not so good anymore. Give me through hole PCB's any day ;) Yes I grew up with vacuum tubes as well.

Is the cost of the new ECU prohibitive? Or are you just a hardcore "I am going to fix this" sort of person like me?
Jon

Sorry I missed something. You reported that you are seeing 12 volts on both of the terminals on one of the Injector connectors with the key on engine off?

No no. If you go through my all my post, you would see that after 2,500 rpm's, one of the injectors stops, and why it stops is because both terminal of the injector ( one that stops) gets 12 volts.

By the way, I am 24 old Electronics engineer, I work with ROVs ( underwater robots). I guess we both share the same passion.

By the way. I live in Chile, we do not get anything here. We have to import everything from other countries. Buying an ECU is very expensive for me. I would just fix this issue anyhow. I will not give up.

Awesome! 55 Year old, Mechanical/Electrical Engineer here. Been making smoke and solder since I was 10! I understand the problem with the ECU purchase. I cannot really advise you on the chip swap though. If you are that industrious and have all the equipment and skills I would say have at it. I am not at all familiar with the chip specs or the ECU internals. Sorry!

Awesome. Nice to meet you (virtually).

Guys, my ECU is broken. What shall I do?

I would try to find a used one, if not you will need to get it programmed should cost about $130.00 to get it done.

Hi Ken,

Someone is selling me a used ECU ( unblocked) , shall I go for it?

There is another one who is selling, ECU, BSI and the keys as well or shall I go for this one?

Regards,

Go for the one with the keys so you will not need any programming. Let us know what happens and please upload pictures or videos of the problem.

I fixed the problem. As all of you guys know Peugeot can be a real pain in arse.
So finally, we revised almost everything in the car. After going through so much, I just made a simple test. I took off the accessory belt and tested the car. Guess what, the problem went away, So I thought , maybe the alternator is messing up and so I installed the accessory belt back and disconnected the alternator wiring , the issue came back, after 2500 rpms , I lost one of the cylinders, then I thought it might be the compressor for the air conditioner so I disconnected that as well, now I have disconnected the alternator and air compressor and still I have the issue where after 2500 rpms , I lose one of the cylinders. So finally I took off the accessory belt and guess what? again the car started functioning alright. Finally, I concluded that as I install the accessory belt irrespective of if the alternator and air compressor is connected or not, I get the issue where I loose the cylinder after 2500 rpms. Then I revised the belt itself and it was stretched a bit and my tensor was bit inside causing the half of belt to run on it, so I changed the belt and the tensor; my car is working A-ok.

The real question, How the hell a stretched accessory belt and a bad tensor can cause a car to loose its cylinder after 2500 rpms, Can anyone explain, please?

Hey SANNKYNM,

P1336 and P1337 are codes for the crankshaft position sensor. Are these the only codes you had? No misfire codes?

The only explanation i can think of initially is that the engine isn't actually misfiring or losing a cylinder. Noise or juddering due to the worn belt slipping or being loose enough to hit other engine components, or the tensioner chattering under load could cause the appearance of a misfire.

The accessory belt running out of line enough to interfere with the crankshaft sensor pickup is potentially possible but i think unlikely. That could cause an engine running issue. What year/engine is your peugeot?

Regards, Joe

Hey SANNKYNM,

Another thought would be to check to make sure the belt had not been contacting any wiring harness that runs near the belt. If the belt had deflected enough to rub through a the harness for the crankshaft position sensor this could also be the cause of your issue. Worth checking to make sure you don't have damaged wiring that will cause you problems further down the line.

Regards, Joe

Hi Joe ,

Thank you so much for your response, I appreciate it and honestly whatever you are saying make sense. My car is a Peugeot 307 1.6 16v 2007 model D-sign break. Its a gasolin car. Hmm in my car the crank shaft sensor is located quite far away from the accessory belt. I dont think it can possibly bother the crankshaft sensor function and I dont see any wiring harness close to the accessory belt. My car runs a-ok now , after 1.5 years I was able to run my car like a normal car. Its a pity because just because of loose accessory belt I spent 1,5 year looking for the problem and almost 1000 usd in replacing parts that had to nothing with the issue. I live in Chile. A good mechanic is like a unicorn.

Regards,

By the way the codes that had had before i resolved it were p1336 p1337 p1338 and p 1339 and I think it was p1340 as well.

Surely I will keep continuing what caused this problem at the first place.

Hey SANNKYNM,

Sorry i missed the previous posts with the check and finding injector shutting down. Unless in replacing the belt you disturbed wiring/ground connection for the crankshaft position sensor/PCM/injector i really can't see why replacing it would fix the fault. With only one injector affected its an interesting fault to have. Very glad to hear it is now running well! hopefully you will eventually get an answer, cars can throw out some mysteries some times.

Regards, Joe

Yes I am glad as well. Thank you so much for giving some thoughts on this mysterious issue.

Regards ,

JOETECHPRO is one of our newest experts and is quickly shaping up to be one of our best :) Please let us know what you find. We are interested to see what it is.

Sure ; I will Ken , you guys have been amazing. Thank you so much for the support.