[Jetmex]

Hello all! So to introduce myself, I am over from the BMW boards and have several BMW Zs. I started and ran the AtlantaZ3 car club for years before moving to Memphis where I am now. I just acquired a 2009 Smart ForTwo here in the US and got it because it doesn't run and had been parked in the weeds for about 6 years. To put it bluntly, I am rescuing it from a horrible death. I have stripped the interior out to dry it out and if I can get it running will start prettying it up.

So on to my issue (and thanks in advance),

451 gas powered 1.0 liter

The car cranks and coughs once but does not start/run. Each key cycle does the same thing, one cough and a no start. I pulled the fuel line off and pressure seems to run about 45-50psi (maybe). It seems the pump is putting a steady flow of fuel into the fuel rail while cranking. I pulled the fuel rail off the manifold and bagged the injectors and cranked the car again. Initially the injectors spray a nice pulse of spray but after 3-4 good pulses the flow seems to peter out drastically. Does anyone have any ideas? I'm thinking it just isn't getting enough fuel to start and run.

Thank you all again and look forward to being a part of this community,

Greg

 

[Jo e Lefors]

Welcome to SCoA.

 

[Jetmex]

Thanks!

 

[smark]

Welcome to the forum here. Have you hook up a code reader. Might want to see if there are any codes.

 

[XDCX]

I think you're on the right track - the test you did by bagging the injectors provided great information. I agree that it's likely fuel related - best case scenario it's a clogged fuel filter or injectors and worse case scenario it's a bad fuel pump. I doubt it's computer related based on the information you've provided.

I recently bought a 2003 Ford Mustang GT that had been sitting for years and it needed a fuel pump assembly before it would run. The Mustang also hated the old fuel that was in the tank - I drained the tank when I changed the fuel pump and ran the old gas through my chipper/shredder.

If it were me I'd try to get better information concerning the fuel pressure. When I was working on my Mustang I almost bought an OTC Fuel System Cleaner Kit - it's an aluminum canister that you can pressurize with air to clean the injectors while the engine is running. I've heard that some techs will use this to diagnose a bad fuel pump by creating a new source of fuel. I've also heard it can come in handy when you're trying to move a vehicle with a bad fuel pump into the shop.

 

[Jetmex]

Welcome to the forum here. Have you hook up a code reader. Might want to see if there are any codes.

Yup, It's not storing any codes...

 

[Jetmex]

A friend suggested the fuel press regulator may be dumping fuel at start that it shouldn't be. Any ideas where that little booger lives? I thought I found it but now think I found the purge valve on top right side of the engine. I'm just not familiar with this fuel rail system. I'm used to excess fuel being returned to the tank right off the rail.

 

[XDCX]

A friend suggested the fuel press regulator may be dumping fuel at start that it shouldn't be. Any ideas where that little booger lives? I thought I found it but now think I found the purge valve on top right side of the engine. I'm just not familiar with this fuel rail system. I'm used to excess fuel being returned to the tank right off the rail.

Wish I could help but I have no idea where the fuel pressure regulator lives. My gas 451 has been pretty reliable and I haven't had to do any repairs to the fuel system.

Concerning your friend's input - I'd stick with what you saw with the injector bag test. It appears the engine isn't getting enough fuel. Solve that problem and I bet it will run.

Additional thought - have you tried starting fluid at the throttle body?

 

[Jetmex]

Additional thought - have you tried starting fluid at the throttle body?

No, I can get it to run once every now and again. I just had it running and was able to get it to idle without trying to die and save itself, but when I shut it down, It wouldn't restart. It just kept doing the cough and crank thing.

 

[XDCX]

No, I can get it to run once every now and again. I just had it running and was able to get it to idle without trying to die and save itself, but when I shut it down, It wouldn't restart. It just kept doing the cough and crank thing.

It sounds a lot like my Mustang that had been sitting for years. I was able to get it started and it ran just long enough to get it from the street to the driveway and after I shut it off it never ran again until I changed the fuel pump assembly.

Question: Are you trying to get it to run on six year old gas? If so, that alone could be enough to explain the problems you're having.

 

[Jetmex]

Question: Are you trying to get it to run on six year old gas? If so, that alone could be enough to explain the problems you're having.

No that wouldn't be a good thing at all. This was why it was parked in the first place. I'm thinking about dropping the tank tomorrow. Does anyone have any advise for that? Any gotchas I should know about?

Guys thanks for all the comments and advise!
Greg

 

[Jetmex]

So the latest saga... I put a pressure gauge in the system between the input and the fuel rail. Pressure holds steady at about 45psi give or take on a very old gauge. Only varies by a pound or two even when I managed to get it to run briefly. After shutting it off it went back to it's old trick for cough and crank.

So the question is:
1) Why do the injectors initially pulse a decent amount of fuel and then cycle to a lesser amount?
2) Is this a normal part of the fuel injection process?
3) Is this a control problem, sensor problem, or all 3 injectors?
4 Is there a sensor that detects when the eng is/should be running (ie. for the one touch start sequence)?

P.S. the nipple broke off for the vent purge so now I get to purchase a new fuel pump assy.

 

[XDCX]

While I'm no expert, if it were me I'd buy a can of starting fluid and remove the tube to the throttle body and see if the car will run on starting fluid. You'll gain so much information with that simple test.

Concerning your bag test of the injectors, it's possible the pulse width variation you report is normal. It would make sense for a higher initial pulse width to aid in starting and then a smaller pulse width to keep the engine idling. The fact that you've re-tested the fuel pressure and found it to hold steady makes it less likely the no-start condition is fuel related.

I wish could offer more advice but I haven't had any problems with my 451 which would provide helpful information.

 

[Jetmex]

While I'm no expert, if it were me I'd buy a can of starting fluid and remove the tube to the throttle body and see if the car will run on starting fluid. You'll gain so much information with that simple test.

Concerning your bag test of the injectors, it's possible the pulse width variation you report is normal. It would make sense for a higher initial pulse width to aid in starting and then a smaller pulse width to keep the engine idling. The fact that you've re-tested the fuel pressure and found it to hold steady makes it less likely the no-start condition is fuel related.

I wish could offer more advice but I haven't had any problems with my 451 which would provide helpful information.

Wanna pull your fuel rail and check it for me? 😁

 

[the big e]

There is a couple sensors on the engine that work fuel and spark.
It’s possible one of those could be giving false readings.
As far as it not throwing a check engine light well it can still have a code but not trip the light.
I know as mine did a misfire to the point it shut down the no 1 cylinder (trust me that sucked big time as the car bucked like a bronco when just trying to move it) yet not once did it turn on the check engine light.
Get someone with a high end scan tool and see if it will show anything(you can also get live data from the sensors with one)

I think the first spray you see from the injectors is the prime for engine starting then it reduces down for idle till you get into the throttle.
Sounds more like a sensor to me.
Crank sensor or something like that.
Check the wiring harness for chafes and make sure it’s not shorting to ground(engine harness goes up from the engine to the ecu behind the right rear panel)

 

[Jetmex]

There is a couple sensors on the engine that work fuel and spark.
It’s possible one of those could be giving false readings.
As far as it not throwing a check engine light well it can still have a code but not trip the light.
I know as mine did a misfire to the point it shut down the no 1 cylinder (trust me that sucked big time as the car bucked like a bronco when just trying to move it) yet not once did it turn on the check engine light.
Get someone with a high end scan tool and see if it will show anything(you can also get live data from the sensors with one)

I think the first spray you see from the injectors is the prime for engine starting then it reduces down for idle till you get into the throttle.
Sounds more like a sensor to me.
Crank sensor or something like that.
Check the wiring harness for chafes and make sure it’s not shorting to ground(engine harness goes up from the engine to the ecu behind the right rear panel)

Thank you. I'll look into it. I work the next three days, so no tinker time but should be back at it after that. Pulled the codes and it isn't storing anything yet. It has never set the CEL. Yesterday I thought I had it somewhat figured out but then I put on the AC and it bogged down the idle and died. Then it wouldn't restart again, back to it's old tricks.

 

[the big e]

Your going to need a scan tool that can pull live data from the sensors to really see what’s going on since it’s not triggering a check engine light.
I’m still thinking it’s a sensor but without you having access to the data it’s going to be a wild guess.

 

[Jetmex]

Your going to need a scan tool that can pull live data from the sensors to really see what’s going on since it’s not triggering a check engine light.
I’m still thinking it’s a sensor but without you having access to the data it’s going to be a wild guess.

That is my next step for later in the week. Leaning toward an engine computer but that'll have to be a last resort.

Resources sure are slim for these cars. I am so used to BMW where I know all my parts sources and have all the manuals and diag/scan tools. Learning a new marque is not fun at all. I was looking at airflow today learning and realized I didn't have an air meter... Fuel rail is non-return... So many different ways of skinning the cat.

Thank all of you who are trying to help solve my dilemma. It is most appreciated!

 

[the big e]

When it does run does the check engine light come on and stay on?
If so it would give codes(heck it may have codes as it sits as it will trigger a code without lighting up the check engine light)
I would wait till you got to read the live sensor data before ruling out the computer as those aren’t cheap and require programming to work.
The fuel system is pwm(pulse width modulation)
Next time you do get it to run let it run without shutting it off and see how it behaves and how long it runs.
I know what you mean as I came from Cadillac and it being a gm both parts and info was easy to get a hold of.(there is a couple online resources for info on these cars which covers a lot but some stuff I had to figure out on my own)

 

[Jetmex]

When it does run does the check engine light come on and stay on?
If so it would give codes(heck it may have codes as it sits as it will trigger a code without lighting up the check engine light)
I would wait till you got to read the live sensor data before ruling out the computer as those aren’t cheap and require programming to work.
The fuel system is pwm(pulse width modulation)
Next time you do get it to run let it run without shutting it off and see how it behaves and how long it runs.
I know what you mean as I came from Cadillac and it being a gm both parts and info was easy to get a hold of.(there is a couple online resources for info on these cars which covers a lot but some stuff I had to figure out on my own)

When it runs, it runs fairly well. It does not set the CEL nor does it store any codes behind the scenes (ie. codes that don't trip the light). It does seem to stumble around at idle and I drove it last night around the neighborhood. It died every time I stopped but restarted until the last time, when it didn't, pushed it home. I have had it running stationarily for 10-20 minutes. It got warm enough to turn on the cooling fan but still no codes.

Greg