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gauchorojo

Intermittent starting problems

19 posts in this topic

Hi cousins!

Digory, my 2006 Grandstyle coupe with 224k km is having intermittent starting problems.

It happened twice this week, after work, at about 4:30pm both times, and with day temperature highs around 21C/70F.

The first time, on Saturday afternoon, I went to start it, and everything was normal, the engine turned at what appeared to be a normal rate, the battery voltage was 12v, no lights remained on, but it just didnt fire up. Turned the key off, and checked the SGII for codes, none stored. I waited a few seconds, cycled the glow plug twice, just in case, and same results. Tried to listen for the LP fuel pump, but it may have already primed enough pressure, because I didnt hear it. Tried it again a total of about eight times, and then it fired up normally. Sounded completely normal. It run normally (no limp mode), it had no codes stored still, and I drove home normally my 80+ miles home.

On Sunday morning, it fired up normally, and I went to work without any problems. That afternoon, it started normally again!

On Monday morning, it again started ok, and drove to work without incident.

But, in the afternoon, it started after the fourth attempt, and run fine thereon, all the way home.

A little history/background: I drive Digory daily, just over 52k km/32k miles per year. I reinstalled the original LP fuel pump when I upgraded to the 33 litre fuel tank in Mar 2010. It has a two year old alternator, year old fuel filter/separator, intercooler, and Optima Red Top battery, and I blocked the EGR last year. Engine air filter changed in June 2011. Up to now, it has run flawlessly. No CEL, no fuel/water separator or battery light, no codes stored. The battery showed 11.9vdc and 12.0vdc just before it cranked, respectively. The alternator seems fine, since it shows 13.9-14.1vdc with engine running. All fluid levels are normal. No leaks anywhere. Fuel-wise, I used ASTM rated B-5 to B-10, which I splash blend separately in a drum and re-filter with a Goldenrod water-block fuel filter. Glow plug light extinguishes quickly, even in cooler days.

My suspicions, not having looked at anything yet, are as follows:

A. Not enough fuel pressure to start.

B. Not enough heat for startup compression/combustion.

Thus,

1. LP fuel pump in the tank?

2. Glow Plug(s)?

3. HP fuel injector pump?

4. Fuel pressure sensor or pressure bypass valve on common rail?

Unfortunately, there are no 450 cdi smart mechanic shops down here, although I could entrust Digory to my friend and MBenz indy shop owner, but his learning curve is steeper than mine, as I have done almost all the maintenance on Digory, except for a few things Tom has helped me with. Part swapping is not a viable option to fault find either, since I have to get them from you cousins up in Canada or Europe.

Today, I drove to work aboard Kaiser, my '85 MB 300CDT Coupe. A while ago, my wife said it started fine for her, but she did not drive it anyway, JIC.

What is the most reasonable course of action, in your opinions? Where do I start?

Any help will be greatly appreciated.

Regards,

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Gauchorojo, my 2005 Pulse at 68K has also decided not to always start when I need it to and I discovered at lunchtime today that it will start without depressing the brake pedal with the transmission selector in neutral. Has anyone replaced the electrical safe switch at the brake pedal? If so, how much was the part and how long did it take to replace it? Tonight I will replace the ground cable from the frame to the engine in an effort to rule out a potential fault there. Best of luck troubleshooting. I will keep you posted.cappytanjack

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Gauchorojo,I would suspect that the glow plugs or glow plug controller are at fault.Pull the connectors off all 3 glow plugs and with someone turning the key to start you should get 12 volts at each of the connectors.Then measure the resistance of each of the glow plugs, if I remember right they should be around 6 ohms.Tolsen has an excellent post about replacing the glow plugs.The biggest thing I remember from reading it was, if you have to replace a glow plug, start soaking all of them with penetrating oil, lots and lots of penetrating oil and use a T handle not wrench to remove and be very very very careful.CANMAN

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Thx guys!I will ck both items. I have a hunch it will be d glow plugs. I found a great thread here on glow plug replacement, with pictures and all: perfect for a "visual learner" like me :) Does anyone know if d glow plug "controller" is a glorified relay, or is it more modern than that?So, armed with a Fluke I will ck this out tomorrow morning and report findings. I read I am looking for < 1.0 ohm on good plugs, and > or OL on bad ones...Cheers and thx again :)

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Glow plug controller is only what is says it is. Controls pre glow time, keeps glow plugs on during cranking and controls post glow time after engine has started. A good engine should start even with glow plug system completely burnt out unless temperature is below freezing. I suggest you start by measuring compression, perhaps followed up by a leak down test if you find low compression.

A chap named "foler" had a similar start problem which he claimed he solved in the end and he blamed low compression. I never felt I got the full story, perhaps due to the language barrier.

http://www.smartmaniacs.co.uk/showthread.p...arting-problems

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12V seems low for battery. My green car refused to fire about 60K km ago and the battery was 12.2 V Replaced it with a new one and close to two years on it's OK.

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Yeah, a 12v battery should be closer to 13v. If it's at 12v you will have problems. I don't think you have glow plug issues as I can start my car at -5 without plugging in without waiting on the glowplugs at all, crank and start in about 1 second (I forgot to wait this morning...that's how I know). Being where you are and the temperatures you are having problems starting it at leads me to believe it's battery/charging system related. I replaced my battery about a month ago, it was at just a little over 12v but wouldn't start the car, now it's just fine.

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I know from experience that you should also check the grounds above the intercooler fan, they are wired to a stud on the frame above the intercooler on the lip of the engine compartment, there are six or seven of them on one eyelet. Mine corroded and when I removed the fan to clean the EGR they broke off, the car will not start without them ( they are for the fuel pump etc from what I could tell). If e connection is bad it is intermittent in starting ( again know from experience). I had to cut them back about two inches and solder new wires on. I also used one eyelet per wire to make future repairs easier. I have a picture around here somewhere and will post it if I can find it.

Edited by scwmcan

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Found the problem to a cdi with starting issue. After checking multiple possibility, turns out to be a sticky turbo at 50k. Spin it up and off she goes.

That is very interesting! What, if anything can be done to prevent sticky turbo? Just frequent oil changes and proper cool-down before switching off... or?Bil :sun:

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Found the problem to a cdi with starting issue. After checking multiple possibility, turns out to be a sticky turbo at 50k. Spin it up and off she goes.

How a sticky turbo will prevent an engine from starting is beyond me so please someone explain.

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I have 12vdc at each of the three glow plug connectors. Each glow plug had 0.5ohms resistance. Since the vehicle has over 220k km, I will change them anyway. I removed them per the tips and instructions from y'all and links posted. They dont look too bad, but the combustion chambers look sooty as heck. Is this normal? I saw Tolsen's reaming tool, but cant quite tell how the drill bit is secured onto the sacrificed plug. Clarify, please.Thanks a lot to all for your replies. Battery ckd fine, even under load. I think I misspoke when I said "12v". I read 12.8vdc consistently. I guess I rounded it down instead of up, in my rush to post. I do recall on the 8th attempt the first time it gave me trouble, that the SGII showed 11.9vdc, but that was after 7 long attempts to crank. I will definitely look at the grounding bus bar above the intercooler one of you mentioned. I forgot it was even there. I have a set of glow plugs on the way (Thx X 10tothenthpower to Glenn) and will install them next week.Meanwhile I will try cleaning the chambers and look for other possibilities.Cheers,

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Since you have the glow plugs out anyway and a supply of used glow plugs why don't you make one of them into a compression tester fitting?

Tolsen has a picture of his in that post about the reamer, you may have to lengthen it a bit with pipe to make it easier to connect and disconnect the compression tester.

Weld or braze the connections, they will be subject to high pressure.

Make sure your compression tester goes high enough so it doesn't blow up.

Testing the compression will help identify your problem.

CANMAN

***** MAKE SURE YOU GOT ALL OF THE GLOWPLUG OUT, there is an inner part which can separate, compare the plugs to each other and the new ones to make sure they all look the same.

http://clubsmartcar.com/index.php?showtopic=24286&st=20

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II saw Tolsen's reaming tool, but cant quite tell how the drill bit is secured onto the sacrificed plug. Clarify, please.

Posted Image

The sacrificed plug acts as a guide for the 5.5 mm diameter drill. Collar nut brazed to end of drill ensures drill can't be lost into combustion chamber and is also used to turn drill to ream out hard soot. Main reason for choosing collar nut as opposed to as standard nut is I can apply axial load on the collar of a collar nut. This is a much better design and easier to use than any of the commercially available reamers.

Made from my old Beru no 3 glow plug, a 5.5 HSS drill bit and a 10 mm between flats collar nut. Ideally I should have used an 8 mm collar nut but could not find one.

Diameter of tip of glow plug is 5 mm so a 5.5 mm reamer is adequate. Internal diameter of the Beru glow plug housing is 5.5 mm except at the crimp area where the tip enters housing. This means you can make a reamer like the above without a metal working laithe.

Grease the flutes to collect carbon deposit from bores. The carbon will stick to the grease.

How to make one:

1) Sacrifice and old glow plug. Cut off the top bit about 1 mm from housing.

2) Heat glow plug housing until it gets red hot.

3) Fit in a vice with soft jaws and knock out the internal core from above.

4) Drill out crimp area of housing using a 5.5 mm drill bit. Drill will be guided by the 5.5 mm bore.

5) Get an 8 mm between the flats collar nut. Drill out to 5.5 mm bore.

6) Silver solder nut to end of a 5.5 mm drill bit.

7) You may need to shorten glow plug housing a wee for the reamer to reach all the way into the bore.

For further reading click here.

Edited by tolsen

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How a sticky turbo will prevent an engine from starting is beyond me so please someone explain.

I'm curious as well.

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I think I can now explain Foler's intermittent start problem. Foler's Cdi had low compression on number one cylinder. I think his engine had difficulty synchronizing. These engine do not have any cam shaft position sensor. Cam shaft position is therefore sensed by the increase in resistance at compression stroke. This method only works on a single and three cylinder engine. Having low compression on number one cylinder as on Foler's engine will make it harder for ECU to feel its compression stroke and engine may fail to synchronize.

So what can be done?

1) Restore compression on number one cylinder - possible but takes time, effort and parts. Re-bore and new pistons will be required if one cylinder is worn.

2) Fool ECU to synchronize on a good cylinder. Will require lengthening of the leads to injectors. Will it work? I don't know but there sure is a way to find out - try!

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Here is a screenshot of WinStar diagnostic page for engine start:

Posted Image

You will see that my Cdi engine is set up to synchronize on cylinder 1. Battery voltage before start is 12.2 Volt (9 year old battery).

Same screen after engine start:

Posted Image

Engine running. Battery voltage is 14.0 Volts.

Edited by tolsen

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Great post #14, Tolsen!That one should probably by a sticky DIY. Moderators?Now I will have a little project manufacturing a reamer and a compression tester adapter.Thanks for all the inputs and feedback. Once the glow plugs come in and I install them, I will update results.Cheers,

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Great post #14, Tolsen!That one should probably by a sticky DIY.

How about in the "Useful topics" wiki?Where another thread on glow-plug replacement including Tolsens clever reamer already resides under "glowplugs". Edited by Alex

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