Intermittent Fuel Pump

[neilt6 0]

Strange all is fine when you connect block heater. Something is stiff or stuck but gets released by heat or perhaps poor electrical contact somewhere when cold. How about pulling and cleaning some electrical connectors on engine. Do them in turn one after the other and test pump each time. Use an old hairdryer or something to heat the connectors and cable avoiding breaking catches and insulation. Clean externally before pulling.I would limit myself to rail pressure regulator and high pressure pump.Rail pressure regulator is on left side of rail.Something I noticed whilst measuring cylinder compression:Engine will start with both fuel rail pressure and intake manifold pressure sensors disconnected but won't start with disconnected rail pressure regulator so check rail pressure regulator connector first.

Ok, so yesterday I did a little playing around on the engine... I used a heat gun to warm up the regulator and the fuel pressure sensor, and even tried in unplugging them, with no change in behavior. All I got was a check engine light that went out after driving for a bit. Then I tried disconnecting the interior heater, and running the block heater for a few hours and, surprisingly, no change! It looks like it "might" be the interior heater, I'll have to run it seperately and double check, it's possible it started even without the pump all those other times... If it is that what could it be? Faulty SAM?

[Alex 21]

Faulty SAM?

Possible, a lot of stuff happens there. Well worth pulling the plugs, checking for any sign of heat discoloration on the pins/sockets and reassembling. If any damage is seen best solution (short of a new SAM and harness!) is to bend the female side a bit tighter, slide in and out a few times to wipe any corrosion clean and assemble with a product called "Noalox" available at electrical suppliers. Other brands available. It is an antioxidant conductive paste intended mainly for aluminum wiring connections, but works well on all. Use sparingly, be careful with getting excess smeared around. Only that which gets between the mating surfaces does any good, so very little required and pin-point accuracy. A toothpick is the application tool, not an 8" mud paddle! A tiny dab into the female, and slide a couple of times to distribute. It can extend the life of a connector considerably. Is also ideal for the headlight connector, makes subsequent replacements easier. Those connectors can be a bugger to remove.Copper antiseize is a suitable substitute, does much the same job.

[tolsen 630]

Silicon grease in paste or spray form is what I use on electrical connectors. Anything that is conductive may cause leak currents and trouble.

SAM is known to have or develop dry joints. The only way to check is open it out.

An example of a dry joints in SAM is in this thread on OnSmart forum.

[Alex 21]

The "Noalox" is not really conductive in mass, the particles are are extremely fine and suspended in a non-conductive anti-oxidant grease-like substance. The magic happens when it is squeezed between the surfaces of the pin and socket, plating onto the metal and evening out the microscopic roughness, causing an increase in effective contact area as well as preventing oxidation. The stuff really works very well. I've seen a particular connector in a machine I service many of go from about 1 year MTBF to around 3. Very impressive. Part of that is the care with which I repair and assemble, and some I ascribe to Noalox. (It carries rather too much amperage for the size, runs with heat radiated onto and conducted into it, frequent cycling on and off. Piss-poor initial design. Cheap machine, but very popular and works well.)Do use sparingly, certainly not on fine multi-pin communications type connectors, but on higher current connectors prone to the destructive high resistance>heat>oxidation>higher resistance>more heat>etc sizzle and fry cycle it is great stuff. You still have to get the pin and socket somewhat cleaned up and tight fitting again, it won't magically restore a really melted and blown connector, but well applied in an appropriate application it's great.

[neilt6 0]

Good to know, thanks guys. I guess first I'll have to try and heat the interior but not the engine and see if that is indeed the issue. I seem to recall reading somewhere that someone had exactly the opposite problem, using an interior heater caused the engine to crank and not start. That sounds exactly like my fuel pump problem...

[MikeT 744]

Does SAM remind anyone of the HAL 9000?

[neilt6 0]

Ok so this isn't related to the fuel pump, but is related to the end result. Yesterday, my car left me stranded at work because it wouldn't start at -20C after being stopped for 8 hours. It was only like -15C throughout most of the day, so that made me mad to say the least... Anyway, ran the battery dead after only a few tries at cranking it so my dad came and boosted it and it started right away. The engine spun significantly faster while being boosted. So I've started to suspect the battery. Dad wants to stick one in there with the highest CCA possible, so I'd like to get an Optima 34/78. My question is should I get the Red Top or the Yellow Top? What's the real pros and cons of each? I've heard it tossed around on the forums that CCA means nothing on a diesel and you simply need a high AH, but I'm not sure I agree with that...

[bilgladstone 13]

Ok so this isn't related to the fuel pump, but is related to the end result. Yesterday, my car left me stranded at work because it wouldn't start at -20C after being stopped for 8 hours. It was only like -15C throughout most of the day, so that made me mad to say the least... Anyway, ran the battery dead after only a few tries at cranking it so my dad came and boosted it and it started right away. The engine spun significantly faster while being boosted. So I've started to suspect the battery. Dad wants to stick one in there with the highest CCA possible, so I'd like to get an Optima 34/78. My question is should I get the Red Top or the Yellow Top? What's the real pros and cons of each? I've heard it tossed around on the forums that CCA means nothing on a diesel and you simply need a high AH, but I'm not sure I agree with that...

Get the Optima 34R red-top, which has poles in the correct placement for the smart. Reds are for cranking power and yellows are more suited to very deep discharge like high-power ICE.IMHO/YMMVBil

[neilt6 0]

Get the Optima 34R red-top, which has poles in the correct placement for the smart. Reds are for cranking power and yellows are more suited to very deep discharge like high-power ICE.IMHO/YMMVBil

Would the yellow top be better for longevity? What's the price difference between the two?EDIT: I've also heard it said that the car's charging profile needs to be changed on the computer if you switch to an AGM battery like the Optima's otherwise they'll die quickly. Does this affect the smart? Edited January 2, 2011 by neilt6

[neilt6 0]

Ok, it's been a while, but I have some new developments. I unplugged my in-car heater last night and just ran the block heater for the traditional 3 hours at -27C. This morning, the pump didn't run (Well it did, cause I tricked it into running for 5 seconds before I remembered what I was trying to find out) but the engine started without a problem (Except for the starter not engaging the first time I tried). So this leaves me with a few possible solutions:1. The problem is inside the cabin2. The fuel pump never ran even with the in-car heater plugged in, I just didn't notice over the noise of the heater3. They're all programmed to do that and it's just not starting because it's a diesel and it's coldDo you think you guy's could listen and see if your pump runs the next time it's cold out (Around -20C is usually where it doesn't seem to work). Thanks in advance. I'm taking a soldering course as a component of my Computer Engineering Technology course at NAIT so maybe after this semester I'll be able to crack open the SAM and do some re-soldering.

[Huronlad 186]

My fuel pump always runs after sitting overnight, even down to around -35.

[neilt6 0]

My fuel pump always runs after sitting overnight, even down to around -35.

Ok so definitely abnormal, thanks. Can you start it at -35C without the block heater?

[Huronlad 186]

No block or oil heater, cycled the glow plugs 2 or 3 times and she fired up.

[neilt6 0]

No block or oil heater, cycled the glow plugs 2 or 3 times and she fired up.

I'm jealous, want to trade? Mine almost wouldn't start at -16C the other day after being left for only 7 hours. Ran the battery completely down cranking and cycling the pump/plugs and then let it sit. Then tried again 5 minutes later and it finally went on the last few cranks of the battery.

[MikeT 744]

I presume that was before you realised the battery was half dry? I bet it's toast, you should change it.

[neilt6 0]

I presume that was before you realised the battery was half dry? I bet it's toast, you should change it.

Yes it was, how much would a battery that's low on water affect the crankability?

[neilt6 0]

New developments guys. I saw a video on YouTube where the guy's car barely started kindof like mine and he determined it was because of his PowerBox CR. Anybody have experience with these units and know where I could check for one from the previous owner?

[MikeT 744]

Battery V on a half dry battery isn't going to be good! Yes, starting will be affected!

[neilt6 0]

Battery V on a half dry battery isn't going to be good! Yes, starting will be affected!

I thought so. It showed 11.6v yesterday after the episode on the highway. We're going to get the battery load tested today to see if it's still ok.

[Huronlad 186]

If the battery can only be charged up to 11.6 Volts it is time for a new battery.

[neilt6 0]

If the battery can only be charged up to 11.6 Volts it is time for a new battery.

No it was 11.6v before charging.

[ianjay 6]

HelloNow that the cars are getting older, many of the electrical problems that affect driveability are the result of weakened batteries. You seem to have a bunch of issues, and the simplest thing is to replace the battery (without going to the dealer and having the car properly diagnosed). smarts are very sensitive to voltage, and moisture issues that affect grounds and connections. Your problems may disappear altogether. I wouldn't go looking to replace anything else without making sure you have the volts and the charging capacity to keep them where they need to be.Ian

Edited January 12, 2011 by ianjay

[neilt6 0]

HelloNow that the cars are getting older, many of the electrical problems that affect driveability are the result of weakened batteries. You seem to have a bunch of issues, and the simplest thing is to replace the battery (without going to the dealer and having the car properly diagnosed). smarts are very sensitive to voltage, and moisture issues that affect grounds and connections. Your problems may disappear altogether. I wouldn't go looking to replace anything else without making sure you have the volts and the charging capacity to keep them where they need to be.Ian

Unfortunately that's not the simplest thing when the replacement battery is $250, and this one is only 6 months old.

[bilgladstone 13]

Unfortunately that's not the simplest thing when the replacement battery is $250, and this one is only 6 months old.

Is that price for an OEM replacement battery!? Get a spiral cell AGM battery like this one from CTC for under $200 and install it yourself - easy to do!

Provides up to 770 CCA10-year total warranty, 3-year free replacement, and 3-year power assist periodOffers 17 times the vibration-resistance of conventional batteries (vibration is a major contributor to battery failure)Tightly wound cylindrical cells give added performance and durability. Delivers up to 30% more cold cranking amps during the first five critical secondsMaintenance-free - completely sealed configuration recycles hydrogen and oxygen - no spills, no gas, no need to ever add waterUses AGM technology - battery acid is completely absorbed into cell materialIdeal for regular vehicles, but can also be used for the most demanding vehicles

Bil

[tolsen 630]

A Bosch or Varta type 065 battery is only 50 GBP so no more than 77 CAD.