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Fri May 04, 2012 2:28 pm

I have a quick question for the group. What would cause an FI engine to not start when warmed up, but IF you ICE down the intake manifold it'll start right up and run. Note, this car is also currently running rich (getting about 20mpg), and is about 650 miles away from me, and I'm trying to help someone who doesn't have internet access at the moment. I've looked thru the Elfrink manual, but there's nothing in it about "no hot starts", only no cold start. Any ideas that you can give? He's only got a minimal tool kit with him. Thanks for any help.

Fri May 04, 2012 2:50 pm

Bobnotch wrote: I have a quick question for the group. What would cause an FI engine to not start when warmed up, but IF you ICE down the intake manifold it'll start right up and run. Note, this car is also currently running rich (getting about 20mpg), and is about 650 miles away from me, and I'm trying to help someone who doesn't have internet access at the moment. I've looked thru the Elfrink manual, but there's nothing in it about "no hot starts", only no cold start. Any ideas that you can give? He's only got a minimal tool kit with him. Thanks for any help.

Tell him to unplug the temp sensor in the intake and try it. I'm assuming it's a '70- 73?

Fri May 04, 2012 2:54 pm

Tram wrote: Bobnotch wrote: I have a quick question for the group. What would cause an FI engine to not start when warmed up, but IF you ICE down the intake manifold it'll start right up and run. Note, this car is also currently running rich (getting about 20mpg), and is about 650 miles away from me, and I'm trying to help someone who doesn't have internet access at the moment. I've looked thru the Elfrink manual, but there's nothing in it about "no hot starts", only no cold start. Any ideas that you can give? He's only got a minimal tool kit with him. Thanks for any help.

Tell him to unplug the temp sensor in the intake and try it. I'm assuming it's a '70- 73?

I had just suggested that when I talked to him right before I posted the above. I also warned him it might run rich, but it's already running rich.
It's a 71, running the C-D FI system. All stock, with a 1600, and the cold start completely disabled.

Sun May 06, 2012 10:32 am

He got home late last night. Hasn't had a chance to go thru everything to find out the cause, but it did need 2 hours to cool down between stops. It was still running rich though. The general consensus on the type 3.org list was either a cracked diaphram in the MPS, or a FPR that took a crap. At this point, we don't know which it was, or IF it was either one.

Brian (aka 66311), thanks for the offer to let him stop by so it could get looked at,8) but he just went thru to his next fuel stop, and spent the night there. Then pushed on the next day. Other than it running rich, and the hot hard start, the car ran great. :D

Sun May 06, 2012 12:32 pm

Bobnotch wrote: He got home late last night. Hasn't had a chance to go thru everything to find out the cause, but it did need 2 hours to cool down between stops. It was still running rich though. The general consensus on the type 3.org list was either a cracked diaphram in the MPS, or a FPR that took a crap. At this point, we don't know which it was, or IF it was either one.

Brian (aka 66311), thanks for the offer to let him stop by so it could get looked at,8) but he just went thru to his next fuel stop, and spent the night there. Then pushed on the next day. Other than it running rich, and the hot hard start, the car ran great. :D

I'll bet it's a temp sensor. I don't see any way that the car can "run great" with a vacuum leak at the MPS or bad pressure regulator.

Sun May 06, 2012 6:06 pm

Tram wrote: Bobnotch wrote: He got home late last night. Hasn't had a chance to go thru everything to find out the cause, but it did need 2 hours to cool down between stops. It was still running rich though. The general consensus on the type 3.org list was either a cracked diaphram in the MPS, or a FPR that took a crap. At this point, we don't know which it was, or IF it was either one.

Brian (aka 66311), thanks for the offer to let him stop by so it could get looked at,8) but he just went thru to his next fuel stop, and spent the night there. Then pushed on the next day. Other than it running rich, and the hot hard start, the car ran great. :D

I'll bet it's a temp sensor. I don't see any way that the car can "run great" with a vacuum leak at the MPS or bad pressure regulator.

The thinking on the FPR, was that it was failing in a way that was allowing the pressure to rise during "hot start". It's already been noted that 1 of the list members (Keith Park) has already had that type of failure (on a road trip), so it's at least plausable. He was having the same running rich issue as well, but the car ran great at highway speed. No one in the group that was running with him, had ever seen that happen before (4 of the guys were experienced with FI including Russ). :shock:

Sun May 06, 2012 6:46 pm

Bobnotch wrote: Tram wrote: Bobnotch wrote: He got home late last night. Hasn't had a chance to go thru everything to find out the cause, but it did need 2 hours to cool down between stops. It was still running rich though. The general consensus on the type 3.org list was either a cracked diaphram in the MPS, or a FPR that took a crap. At this point, we don't know which it was, or IF it was either one.

Brian (aka 66311), thanks for the offer to let him stop by so it could get looked at,8) but he just went thru to his next fuel stop, and spent the night there. Then pushed on the next day. Other than it running rich, and the hot hard start, the car ran great. :D

I'll bet it's a temp sensor. I don't see any way that the car can "run great" with a vacuum leak at the MPS or bad pressure regulator.

The thinking on the FPR, was that it was failing in a way that was allowing the pressure to rise during "hot start". It's already been noted that 1 of the list members (Keith Park) has already had that type of failure (on a road trip), so it's at least plausable. He was having the same running rich issue as well, but the car ran great at highway speed. No one in the group that was running with him, had ever seen that happen before (4 of the guys were experienced with FI including Russ). :shock:

you know the more time I spend around this system the more I hear about random 1-off failures leading to wtf situations. its kind of depressing.

in any case, I don't think it could be a cracked diaphram either. Having had 3 of those now, it wouldn't run well enough to be mistaken for "great", not to mention you'd hear the squealing hissing vacuum leak unless you were completely tone deaf to how your engine sounds.

the only other thing I can think of is the head temp sensor and or wiring.

Tue May 08, 2012 8:28 pm

My second to last ECU stopped working when I crossed a couple of wires in the harness. Sent it to Fuel Injection Corp. in Livermore, Ca, and they 'rebuilt' it with fresh paint and whatever else they do for $215. I received it back 10 days later, and it worked. 18 month warranty, void if cover is removed.

1/2 the price for MegaSquirt, but completely non-stock.

They also say that they rebuild MAPs for d-jet.

According to the dude, they bought Brett Ent, 20 years ago.

http://www.fuelinjectioncorp.com/

Wed May 09, 2012 4:18 am

Hi, I have a Australian '70 fastback. I've owned it for about 2 years and the whole time it has had problems with cold starts.
For a while I was convinced it was the AAR as it was broken and wouldn't lock into place - but then I bought another and no difference. As a test I disconnected it when cold and the engine started racing - so I know it is doing it's job.

The problem is this;
On stone cold the first cranks there is nothing, then I'll get a odd catch.. then catch and a splutter .. then splutter splutter .. then finally she will run - once it catches it runs absolutely fine with no hesitations and very smooth.

I'm guessing the reason it goes through the above process is when there is enough heat from the attempted starts it will run fine.

I've had the engine out and when installing could only see 2 possible anomalies - shown in the pic below

1) The red wire was unplugged and going to nothing - green is plugged in.. what are these for and are they important.

2) under the air cleaner is a bunch of white wires earthed in a multi plug.. one wire had stripped itself from the plug.

Wed May 09, 2012 9:43 am

Green wire: to oil pressure light sender

Red wire: only used on late automatics-- clipped from the factory fot stickshift cars

White wires on "porcupine": These are injector and system grounds, and a broken wire will cause all or some injectors to fail to squirt. Make SURE these are all clean and tight.

Thu May 10, 2012 4:01 am

Great thanks for that - I'll get that white wire remedied. Any ideas for cold start issue? It's in all temps that it happens.

Sun May 20, 2012 11:26 am

Recently bought a 70 sqback that hs been stored for 30yrs. The injector wiring was not in the best shape. Dropped motor cleaned it up and found an engine harness from a friend. Has extra wires not sure of and the engine has conector the old harness didnt have plugs for nor the new one. Anyone have good pics of the right side wiring? I have 2ea 2 prong plugs but have 3 spots for them. will get pics asap of problem areas

Sun May 20, 2012 1:50 pm

marchi wrote: Recently bought a 70 sqback that hs been stored for 30yrs. The injector wiring was not in the best shape. Dropped motor cleaned it up and found an engine harness from a friend. Has extra wires not sure of and the engine has conector the old harness didnt have plugs for nor the new one. Anyone have good pics of the right side wiring? I have 2ea 2 prong plugs but have 3 spots for them. will get pics asap of problem areas

It sounds as if you maybe have the wrong year harness. Yes, get us pics, please. I have some complete 1970 harnesses stashed away (I think) and a NOS Bosch reman C ECU still in the box if you're interested.

Mon May 21, 2012 7:53 am

i have a 69 type three that i had originally planned on convering to carbs but have decided against it. the car was sealed away in a garage for 33 years until i aquired it last year. so far ive rebuilt the fuel pump and ive pulled the injectors and im getting spray but it does not run off the injectors we had it running but we had to add gas directly in the throat. hoping you had some ideas.
Andrew

Mon May 21, 2012 8:08 am

My daughter has a 72 FB with FI and 3 speed auto. As she was driving the other day, it started to get sluggish. It ended up slowing down to about 10 MPH then stopping completely. When I got to her, I managed to get it stated and limed it home. It was very sluggish, backfiring occasionally and died in the driveway. I got it started this morning, but barely kept it running by pumping the throttle. I used to work on VW's a lot, but it's been 20+ years. My first thoughts would be timing. The distributor is nice and tight, so I don't think it's turned. It has new dist. cap and rotor. Just ordered a Bentley for it, but would like to fix before it arrives. Not sure if this is related or not, but before this the top speed was limited and was kind of sluggish when it's hot outside (we are in Florida) and the car was super peppy after a rain had cooled things off. Any help would be appreciated!

Mon May 21, 2012 9:14 am

Tram wrote: marchi wrote: Recently bought a 70 sqback that hs been stored for 30yrs. The injector wiring was not in the best shape. Dropped motor cleaned it up and found an engine harness from a friend. Has extra wires not sure of and the engine has conector the old harness didnt have plugs for nor the new one. Anyone have good pics of the right side wiring? I have 2ea 2 prong plugs but have 3 spots for them. will get pics asap of problem areas

It sounds as if you maybe have the wrong year harness. Yes, get us pics, please. I have some complete 1970 harnesses stashed away (I think) and a NOS Bosch reman C ECU still in the box if you're interested.

and shameless plug: I make new ones if you're interested.

Mon May 21, 2012 9:16 am

annen0017 wrote: i have a 69 type three that i had originally planned on convering to carbs but have decided against it. the car was sealed away in a garage for 33 years until i aquired it last year. so far ive rebuilt the fuel pump and ive pulled the injectors and im getting spray but it does not run off the injectors we had it running but we had to add gas directly in the throat. hoping you had some ideas.
Andrew

what is the spray like? do you know what fuel pressure you have? what is the voltage? low voltage can cause it to run so rich (or rather than a mist, dribbles of fuel) it floods and won't start.

check the voltage while cranking

check your fuel pressure

re-check all your ignition stuff (points closed?)

report back 8)

Mon May 21, 2012 9:18 am

OVIEDOAV wrote: My daughter has a 72 FB with FI and 3 speed auto. As she was driving the other day, it started to get sluggish. It ended up slowing down to about 10 MPH then stopping completely. When I got to her, I managed to get it stated and limed it home. It was very sluggish, backfiring occasionally and died in the driveway. I got it started this morning, but barely kept it running by pumping the throttle. I used to work on VW's a lot, but it's been 20+ years. My first thoughts would be timing. The distributor is nice and tight, so I don't think it's turned. It has new dist. cap and rotor. Just ordered a Bentley for it, but would like to fix before it arrives. Not sure if this is related or not, but before this the top speed was limited and was kind of sluggish when it's hot outside (we are in Florida) and the car was super peppy after a rain had cooled things off. Any help would be appreciated!

sounds like a temp sensor is out of whack, or the MAP has taken a dump.

you need to start at the beginning and check your valves, the voltage in the charging/ign/FI power relay circuits, make sure none of your vacuum hoses are leaking, but if you don't have the bentley you should wait until you have it.

Mon May 21, 2012 9:22 am

Great, thanks. I did just fine a cracked hose to distributor and replaced. That helped some but didn't do it totally. I will wait on the maual, as I don't even know what the rest of those parts are lol.

Mon May 21, 2012 9:33 am

Plugged gas filter or screen in the gas tank.