Dodge Repair: cold starting problem

Question
QUESTION: I have owned this 91 b350 1ton maxi van for over 15 years. never had any problems starting outside in Mn. Last year when temp dropped below about 20 it turned over great but would not start. I have replaced alt.,coil,starter,battery, and inst. tank heater. The only thing that has worked is putting a small space heater under the hood blowing toward the intake for 5 to 10 minutes. if I don't start it about every hour when i'm on a job it won't start. Hope you can help. It has somekind of carb. conversion injector. I think it is a fuel prob. but don't know where to start.

ANSWER: Hi Bill,
What size (L) engine is it and is the "carb conversion" done by Dodge?
I don't have manuals for maxi-vans from the 90's so am limited on details. But it should have built-in self-diagnostics. Turn the ignition key "on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the check engine light, which remains "on", to see it begin to flash, pause, flash, etc. Count the number of flashes before each pause. Then repeat to be sure of an accurate set of flash counts. Let me know the counts in order of appearance and we'll go from there.
Roland

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QUESTION: Hello again Roland. I sent in this question awhile back but the problem quit happening but now it is back.  It is a 360 Ram 350. I believe the carb conversion is original.  the count is:  On P 3 P 3 P 7 P 5 P 5 P  Hope this helps to solve. Have no idea what it can be. Thanks for your help  Bill

ANSWER: Hi Bill,
The fault codes have 2 digits so there should be 2, 4, 6, etc. counts, whereas you only showed 5 counts. There should be a pause in one of those flash counts, so try it again. The last two counts of 5 and 5 are correct which is the code number 55 for "end of readout". So see if either 3 could be a 1 and 2, and a 1, or if the 7 could be split with a pause.
Roland

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QUESTION: hey it's Bill again. Hope this one is closer.  1 P 2 P 3 P 7 P 5 P 5  Tks

Answer
Hi Bill,
None of the codes would affect cold starting. The 12 means the battery was disconnected recently. The 37 is about the torque converter clutch solenoid on the automatic transmission (if you have one, but in any case would not impact starting), and the 55 confirms "end of readout".
The main possibility for a no/hard start with no fault codes is that the exhaust gas recirculation valve (egr) may be stuck slightly ajar which then leans the mixture too much to sustain an idle. Look for such a valve to mounted at the far end of a narrow exhaust pipe which branches off the middle of the exhaust manifold (usually the right side manifold) and goes toward the throttle body. It has the body of the valve connected to that pipe, a round top with a vacuum hose, and a flange between the top and the body. Hidden behind that flange is the valve stem which can be moved back and forth with the tip of a screwdriver inserted into the slot that circumscribes the stem. Internal spring-action should close the valve to a dead stop. If it is gummed up then spray some WD-40 on the stem where it enter the body of the valve and then move it some more to loosen the action.
That is my best suggestion for this situation.
Roland