No warm start!!??
Thread Starter
Pro
Joined: Dec 2000
Posts: 534
Likes: 32
From: Farmington NY
No warm start!!??
I have an 85 with 90K miles. It has run well for years. The end of this summer I began to have some problems with it. Starts great in the morning when I get ready to go to work but I stop for gas or anywhere and shut it off to run in a store or something it won't start again! Has to sit about 20 minutes (as long as I don't crank and drain the battery!). I've found if I pull the intake hose and spray some starting fluid it will fire. I checked the fuel pressure when it started and I found it was way too high. Now I've got that adjusted to about 43 but I'm still encountering the same problem! What should I do??
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
First check for stored codes. You must have spark since you can start with starting fluid although you may have weak spark. You should have easily 1/2 inch of bright snappy spark. I would check spark engine hot. Weak spark hot most likely is the spark module in the distributor. Next time it won't start, unplug the MAF and try a start. If it starts you have a defective MAF.
Thread Starter
Pro
Joined: Dec 2000
Posts: 534
Likes: 32
From: Farmington NY
Okay, I guess that was a slight help, I checked the plugs and guess they were in tough shape, 1st off, wrong ones, they were too hot, 44 vs 43s which is what I replaced them with. Seems to run okay, starts fine after I stop everythings looking good. Wait, I guess that's not the case! Short idle and it stalls, will restart right up but idle at a stop sign, stall again! What is the problem! I don't want to put it away for the winter with a problem. The leaves are falling off that shade tree (yea, I'm not a real mechanic) so I have to look to you more knowledgeable types to solve my problems. It's work for the last few years. I've owned the since it had 29k and you've helped me through injectors (could that be an issue again) ball joints and brakes.I've learned a lot but am not a great diagnostitian! Where do I go from here? Thanks for any insights.
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
Could be a few things. You have a FP gauge, so thats a good start.
85 fuel pressure should be 34-39 during priming and 30-36 while idling. I think the first thing you should do is find out why yours is so high.
EDIT::: I took a quick glance at my FSM. The flowchart for pressures above normal range lead through a few different checks. THey end at either a restriced fuel return line, or a faulty pressure regulator. If you don't have the book, maybe you can ask Agent86 for a scan...
85 fuel pressure should be 34-39 during priming and 30-36 while idling. I think the first thing you should do is find out why yours is so high.
EDIT::: I took a quick glance at my FSM. The flowchart for pressures above normal range lead through a few different checks. THey end at either a restriced fuel return line, or a faulty pressure regulator. If you don't have the book, maybe you can ask Agent86 for a scan...
Last edited by mikey whipreck; Oct 9, 2006 at 10:55 PM.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
You can take the ignition module out and have it tested at Autozone for free. Also you can check to see if the injectors are leaking, by using the fuel pressure guage after shutdown. And might want to ohm the injector coils.
Drifting
Joined: Feb 2006
Posts: 1,263
Likes: 0
From: CV ca
St. Jude Donor '11-'12-'13
Originally Posted by jfb
First check for stored codes. You must have spark since you can start with starting fluid although you may have weak spark. You should have easily 1/2 inch of bright snappy spark. I would check spark engine hot. Weak spark hot most likely is the spark module in the distributor. Next time it won't start, unplug the MAF and try a start. If it starts you have a defective MAF.
I've had both of these things happen at different times. The real pain in the butt was the ignition module. 
I still had spark so at that point I started looking towards fuel. While checking other things, it was enough time to cool down, and it would start. I could also start it with starting fluid......for a while. Finally ended up coming home on the hook one day.
So don't put off checking your module before you spend a bunch of money on other things.(like I did) 
good luck.
Bryan
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Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Originally Posted by Da Mail Man
......if it's a hot start problem, the cold start injector is "off" as it only comes into "play" when engine temp is below 95*.....doubt that is it....
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Next time it does this hold the gas pedal to the floor, if it starts easier then I'd suspect leaky injector(s), holding it to the floor will put it in clear flood mode.The ICM would be the next thing I'd have checked.
Drifting
Joined: Aug 2002
Posts: 1,775
Likes: 125
From: Birmingham AL
Does the fuel pressure stay steady after shutting the pump off? It should slowly- very slowly drop. Mine would drop instantly and turned out to be a split fuel pressure regulator diaphragm. It was pumping fuel into the plenum through the vacuum hose. Difficult to start when warm and ran out of fuel quickly.
