230e cranks but no start

Post by **hyjinx** » Tue 20 Jul, 2021 7:05 pm

hi,

ive been fighting with my 230e for a few weeks. undriven for a few weeks i tried to kick it over and it cranks but no fire.
so i changed plugs no change. couldnt get any leads or a dizzy cap but got another ignition coil recieved it and it was a mirror image to my one but i installed it and didnt seem to change anything. managed to get a dizzy cap (got a rotor button also) it fits but the beru one i removed doesnt have firing order on it and this one does. set it up how i think should have gone no change.

help please need ideas options solutions.

Post by **Christo C** » Tue 20 Jul, 2021 7:59 pm

Why do you assume it’s an ignition problem?
Have you checked you are getting a spark at each plug?
Do that by connecting plug lead to an old plug, earthing it to chassis and have someone attempt to start while you observe spark across plug, preferably in a dark place. (Better to do that than remove plugs and risk fire).
Do you hear the Fuel Pump burst into life as you attempt to start?

Post by **hyjinx** » Tue 20 Jul, 2021 8:50 pm

i have tried to check the spark this way but by yourself this wasnt happening.
i went the ignition/spark being the prob because it smelt of fuel in the bay when i was trying to pump throttle and turning key so thought its getting fuel. also i tried some start ya bastard as well and no splutters at all.

i will listen for fuel pump i cant remember if i heard anything or not now.

dizzy cap was looking alittle worn also but im abit worried the replacment isnt the correct one either. is there a way to check the cap with a multi meter?

Post by **Ivanerrol** » Wed 21 Jul, 2021 8:10 pm

Check the C.P.S.
Crank position sensor.
There's You Tubs showing how to do it. You will need a multimeter.

Post by **hyjinx** » Sat 24 Jul, 2021 5:18 pm

on the 4 cyl is the crank sensor pretty much directly under the oil filter?

dizy cap i got has the cylinder numbers on it. the order the leads go on this one when its screwed on puts the leads in a different order to what the previous cap was set up like, that cap didnt have any numbers on it. why and how does this effect the firing order.

Post by **Christo C** » Sat 24 Jul, 2021 5:25 pm

You HAVE to put the leads back EXACTLY the same positions as the original dizzy cap!
The firing order is set by position, not by numbers written on cap.

Post by **hyjinx** » Sat 24 Jul, 2021 9:46 pm

there arent any on the old cap so im screwed.

i didnt put any marks on it when i took it off. i marked the leads and.took a pic afew days before but they werent firing order and have since rubbed off. might be able to work out the leads from theway they were sitting i guess

Post by **Christo C** » Sun 25 Jul, 2021 2:05 pm

Firing order for M102 engine is 1-3-4-2

Post by **hyjinx** » Sun 25 Jul, 2021 3:21 pm

so according to the pelican parts vid and after having a look myself from the top they say easy way to remove crank sensor is from under after pulling starter out. Is it possible from the top?
I've got no line of sight and cant get hand between firewall and oil filter?
Anybody done it from the top?
Problem with going under the car is its parked on the street with a gutter in the way.

Post by **Christo C** » Sun 25 Jul, 2021 3:44 pm

Have you tested the sensor first?
If it measures around 800 ohms it is probably OK. Spec is between 640 & 1200 ohms.
It is the green lead plugged into the EZL Ignition module.
Measure between outer contact ring and centre socket inside the connector.

Post by **hyjinx** » Sun 25 Jul, 2021 4:16 pm

thanks for the info Christo.
So i pulled the plug I'm hoping is the correct one?
It was 899 ohm not cranking and read 1 when cranking (I'm probably not checking it correctly?)

Post by **Christo C** » Sun 25 Jul, 2021 4:32 pm

That’s the one. 899 ohms is in spec afaik.
There’s no point in measuring resistance while cranking; the reading will be meaningless.

Post by **hyjinx** » Sun 25 Jul, 2021 4:42 pm

okay so that means its reading okay?

i have a set of leads on order which is only thing i havent replaced yet. should i try and find a sensor anyway?

Post by **Christo C** » Sun 25 Jul, 2021 4:47 pm

The sensor is just a coil; if it measures in resistance range stated it is probably OK.
If you have buckets of money by all means just keep replacing stuff until you get lucky and solve the problem, but I don’t see the point….
Better to diagnose the fault properly.

Post by **hyjinx** » Sun 25 Jul, 2021 5:18 pm

no buckets of money here and not wanting to ship it to mechanic.
hmm back to the drawing board

Post by **CraigB** » Sun 25 Jul, 2021 8:35 pm

Just picking up on this again..... so in all this, do we know if leads are in correct position? You have the firing order but you need to work out which one is No. 1. You need to get on TDC and then see if valves are rocking on 1 or 4. If its 4 then 1 should be firing and dizzy pointing to that lead, Then just put the rest in order.

Post by **hyjinx** » Sun 25 Jul, 2021 8:56 pm

they were prior and after the plugs and coil were changed and nothing changed from those being changed. since the new cap is when i friged the leads around on the cap.

so no i dont know if the way i have it atm is correct.

Post by **CraigB** » Sun 25 Jul, 2021 10:31 pm

ok, so do my instructions to check make sense? should only take minutes and you just have to make sure your basics like that are correct. Just trying to help someone on another forum and saying that I learnt that one early on (although it took a while!) , that when chasing problems and particularly asking for advice, you can end up chasing things and each time you change something you are introducing another variable from when it was running.

I agree if starting fluid didn't fire, chances are its ignition. But it is such an easy and conclusive test to pull plug and see if your getting spark. Even if your plugs are in wrong order, it will still tell you if you have spark. Hard if your in lockdown but a neighbour perhaps could turn the key. Also are plugs wet with fuel if you pull them after trying to start, that's pretty good confirmation its ignition. Unlikely all leads will go at once ie. misfire rather than not start. So coil, distributor cap and rotor, crank angle sensor etc are those sort of start/ no start things.

Post by **Christo C** » Mon 26 Jul, 2021 10:12 am

Getting the HT Leads in correct order is not so difficult.
This for my car, a 1986 230E W124, M102 engine, which I assume is pretty close to what you have....

First, lift the Distributor Cap, remove Rotor and the Dust Cap underneath; this should reveal something looking like this:

DistClose.jpg

Notice that on the upper rim of the Distributor Body there is a small cut mark - red arrow indicates - it is small and hard to see if not clean.
That cut indicates that when the Rotor points to that mark the ignition will fire No1 sparkplug.
Therefore note which terminal of the Distributor Cap is directly above this mark. That is Cylinder 1.

Now replace the Dust Cap and Rotor, reassemble the Distributor cap.

The Distributor Rotor rotates clockwise looking from above.
The Cylinders in the motor are numbered 1,2,3,4 from the FRONT of the engine.
Firing order is 1-3-4-2

Connect the HT lead which runs to Cylinder 1 to the Terminal above the mark (as above).
Moving clockwise, that is the terminal for Cylinder 3
Next clockwise is terminal for Cylinder 4
Finally connect Cylinder 2.

Here's a picture of my leads, all numbered.

DistOrder.JPG

Hope that helps.

Post by **CraigB** » Mon 26 Jul, 2021 10:58 am

That is a useful and generous of your time reply Christo. The only thing in my mind, if that doesn't seem to work, is that I think it might still be possible to be reassembled with the gear on the central shaft in a different position and that would throw those things out but still work. So I reckon, most important, are you getting sparks happening at your plugs, then go with that easy process and if that's not working, you can't to wrong with the tdc mark and valves 'rocking'.

Post by **Christo C** » Mon 26 Jul, 2021 11:23 am

Thanks, and correct Craig; however hyjinx has not reported he removed or touched the Dizzy shaft, so have to assume the basic engine/distributor timing has not been altered….

Post by **CraigB** » Mon 26 Jul, 2021 1:27 pm

Absolutely - in the back of my mind was that they are old cars now with potentially lots of owners and also sometimes people search on these threads years down the track, so just chucking the option in there - but agreed, if he checks his against your great photos, its a fast track to hopefully sorting things.

Post by **matthewz108** » Tue 27 Jul, 2021 1:00 am

When checking for spark, and I'm on my own, I turn off lights and set up my phone on video mode in the engine bay, hit record, and you'll see spark if there's any. not sure if you've checked all of the spark plugs? These often tell you if the ignition is or has been working on all 4 cylinders, but if it's not wanting to try to fire up with starter fluid, them sounds like no spark at all. If the leads go back on the same way they came off, and the car was running before, it will be easier to diagnose.

Post by **hyjinx** » Tue 27 Jul, 2021 6:29 am

such great help thanks very much for taking the time to go through all these options and solutions.

got the battery on charge at the moment cause that dead now haha.

ive tried a couple of times now to rig up something to earth the plug in the lead where i can see it through the car as i crank it but to know avail. saying that i was either not able to see a spark because it wasnt ground or it actually had no spark. i will sort this out when i get the battery charged again. when plug is out and car cranking can smell fuel in engine bay. (getting fuel?) also not really hearing any pump action when car is on reds.

correct i haven't messed with the timing ive just removed replaced dizzy cap/rotor button and didnt check lead position (dumbass skills 101).

the car was running no issue (was for sale) and then i didnt touch it for a couple of weeks then it just stopped starting. no misfire or anything like that just crank no fire.

ill update my progress in a few days. thanks heaps again for the tips and info so far. i really appreciate it.

Post by **CraigB** » Tue 27 Jul, 2021 10:45 am

Good idea about working in dark. If you have a misfire that is a great way to find a grounding cable etc. also if you pull all the plugs while turning over, will be easier on battery and you might even hear the plugs clicking.

When car on ‘reds’? Trying to work out the autocorrect on that one. Pump will prime with ignition on but won’t run until motor starts. Can bypass fuel pump relay to make it run but starter fluid etc, prob not it.

I had something similar and it was coil I think. Was off and on prob but worse when air damp.

Post by **Christo C** » Tue 27 Jul, 2021 4:44 pm

As I suggested in my first post, in the dark is best place to test for spark unless you have an inductive timing light.
Use an old plug, plugged into say the lead from cylinder 1, and a normal Jumper lead clamped to the plug body, other end on the Negative of your Battery or some other bolt that is definitely earth/chassis. Keep the wire away from the fan in case the engine starts, albeit on 3 cylinders. Hang the plug on some string from the hood so you can see it from the cockpit through the gap… improvise!
Personally I’d test using the original Coil, DizzyCap & Rotor until I proved any of those were faulty.
If there is no spark the cause could be for other reasons other than bad Coil or Distributor; could be bad EZL module or other factors - beyond my pay level….

Post by **hyjinx** » Tue 27 Jul, 2021 6:23 pm

okay i managed to check spark.

i did all 4 cyl and its got spark. set the leads and dizzy cap as per the images and still no fire. the plugs smelt like fuel didnt seem wet tho.

im definitely not hearing fuel pump noises on reds.

Post by **Christo C** » Tue 27 Jul, 2021 6:43 pm

I’d be looking at Fuel Pump Relay next, also fuse on top of adjacent OVP (over voltage protection) Relay… after that, who knows…
Both located behind Battery.

Post by **hyjinx** » Tue 27 Jul, 2021 7:17 pm

you should change your name to haynes. ill seek those out next.

Post by **matthewz108** » Wed 28 Jul, 2021 12:40 pm

When checking fuel supply, check that fuel pump is getting voltage, you can remove the fuel pump relay and jump it so the pump gets 12v constant on ignition on (can't recall which pins to jump, but that's easily googled). If it's getting 12v when jumped, then it's your relay. if it's not, then there's a power supply problem, so you need to check if you're got 12v coming into the fuel pump relay etc.
As far as i know, the fuel pumps normally don't run continuously unless you're cranking. They normally come on for a few seconds with ignition on (but not cranking) then switch off. By jumping the fuel pump relay, the pump will run continuously with ignition on.
I do hope this isn't something really simple that we're all missing...

Post by **hyjinx** » Wed 28 Jul, 2021 9:55 pm

hehe me also. i did check its in park

Post by **hyjinx** » Thu 29 Jul, 2021 5:03 pm

so i think you guys have solved my saga.

i made a little bypass cable with some wire and crimped some ends on. the 3rd pins along top and bottom from the right side are the ones that need jumping on the fuel pump relay.

plugged them in fuel pump kicked in straight away. i jumped in car and cranked it for a few seconds and BAM fired up.

looks like the firing order 8s sorted also as it run super smooth.

cannot thank all you guys enough it did my head in. this is my 3rd merc and the only one ive ever had starting issues actually any running issues with. Off to find a relay now.

Post by **Christo C** » Thu 29 Jul, 2021 5:25 pm

Do not discard the old relay!
They are known to develop dry joints in the internal soldering esp around where the pins meet the cct board.
I have two which had that problem; eminently repairable with a little soldering skill.
If you have trouble with doing that, pm me and you could post it to me….
Certainly worth a try …

Post by **matthewz108** » Thu 29 Jul, 2021 6:31 pm

Great news.its funny how sometimes you can work on the ignition system, then the fuel pump relay goes, and you automatically think it's related to what you're working on.

Post by **hyjinx** » Thu 29 Jul, 2021 8:08 pm

my guess is it was this from the beginning but it now has a bunch of newnstuff that ot was probably needing as well.
i definitley wont get rid of the relay keen to learn some more about this bastard.

Post by **hyjinx** » Thu 29 Jul, 2021 8:08 pm

my guess is it was this from the beginning but it now has a bunch of newnstuff that ot was probably needing as well.
i definitley wont get rid of the relay keen to learn some more about this bastard.

Post by **CraigB** » Thu 29 Jul, 2021 8:28 pm

Good news. I understand you can get a fuel smell off the prime, but I wonder why it didn't kick on starter spray?

Post by **hyjinx** » Thu 29 Jul, 2021 10:30 pm

yeah i dont know i was doing it by myself so maybe it wasnt quick enough to crank after i sprayed it ????? who knows. normally it would set you straight pretty fast.

Post by **hyjinx** » Fri 30 Jul, 2021 10:30 pm

so while i wait for the relay. i put my new wheels on which I refurbed prior to all this shite lol looks alot better

Post by **hyjinx** » Wed 11 Aug, 2021 8:40 am

what if any are the differences between these 2 parts?

Post by **Bartman4800** » Wed 11 Aug, 2021 10:16 am

Well, my knowledge of German is sufficient to tell you the bottom one is a relay for a fuel pump for a 12V system.

The PA6-GF30 means it's made of nylon (Polyamide) with 30% glass fibers.

Now over to someone else who can compare the part numbers.

Bart

Post by **Christo C** » Wed 11 Aug, 2021 10:41 am

They are the same; I have the 89 8174 000 fitted to my 230E now, and the other as a repaired spare; both work the same.

Post by **hyjinx** » Wed 11 Aug, 2021 6:30 pm

awesome the only 1 i could get was the 003 and it worked and i wanted to know if it did anything different.

Post by **Christo C** » Wed 11 Aug, 2021 7:24 pm

As far as I know
Bosch 89 8174 000
and Merc Part Numbers
002 545 21 05
003 545 20 05
003 545 19 05
are all equivalent.

Post by **hyjinx** » Thu 12 Aug, 2021 8:39 am

thats good enough for me. the old part was working again so it wasnt to worrying. im glad its the same i was worried something would be slightly different in the config and it just not work at all.

thanks yet again