My 1996 deville, 80,000 miles, is hard to start. If the engine is warm, no problem, starts right up. But if the car sits for a whlie, and the engine gets cold, then it takes a lot of cranking to get it started.

Does anyone know what is the problem.

I am thinking fuel pump pressure is low.

Mike in Wexford PA, 17 miles north of Pittsburgh.

 

Start easy at the 2 filters, air and fuel then spark plugs, then wires. Sounds like you have plenty of cranking amps in your battery but make sure the connections are good especially the ground.take them off the battery and clean them, re-attach nice and tight.I would not jump to the fuel pressure which is the sending unit AKA pump right away but a mechanic can test that for you.

 

Hey Mic: The condition you explain is a classic example of an open circuit in the engine coolant temp. sensor, which is hard start when cold but fine whenhot. Hope this helps.........................................

 

Do you know how to acess the PCM codes? The problem brougham1 points to should show up as an error code. Check for codes and post or let us know and we will telll you how to get them.

 

Thanks for responding to my post. I pulled the codes from the Dashboard Readout feature. Here is what I got
PC0603
AC1347
RS0013 history
RF2560 history

Can you let me know what they mean.

I live in Wexford PA, 17 miled north of Pittsburgh. 96 Pearl White Deville with only 80,000 miles. The car is like new, inside and out. I want to keep it a while longer, but I need to fix the starting problem before it gets worse and I get stranded.

Thanks for you interest.

Regards,

Mike

 

I hope some one else has access to these codes because I am not that familar with them other than to tell you that AC1347 is Very Low Refrigerant, RS0013 is a road suspension system code ans RF2560 is a radio code. The PC0603, looks like a memory issue but can't be sure.

Anyway, it is the coldest winter in 28 years, I think your battery may be weak. When you drive around it gets charged upby charging system and when it sits it goes flat. This would be consistent with what you describe.

 

It would also help to have some description of the cranking involved. When the engine is warm, it will generally crank very quickly. When it is cold, if you have a weak battery (or a battery that is not up to a high standard) that can cause a slower cranking speed. I develop and calibrate engine management systems for a living, and one thing I can tell you from my development work is that these distributorless ignition systems generally require a certain cranking RPM before they can work. In the days of carbs and distributors (or even just some of the earlier EFI systems out there), you could have an engine that would fire with just a tap of the starter. Modern systems don't offer that, but what they do tend to offer as an advertised advantage is consistent starting.

If your cranking when cold is more of a craaaaaaaaaank-craaaaaaaaank-craaaaaank as opposed to the hot start crank-crank-crank, and when cold the more you crank it the faster the engine spins, that could be your issue. On my Town Car (which utilizes a completely different system, but that runs off a similar concept), one night when I'd worn the battery down a bit that's how it cranked, and it had to crank over a few times to the point where the engine reached the minimum starting RPM. If this is the case, I would suggest getting a battery with a higher CCA rating (I put the highest I can find in all my vehicles).

If the cranking is as it's supposed to, one test you can try if you think it's fuel pressure is tapping the starter a few times when it's cold. On most systems this will cause the fuel pump to run for a bit, building up pressure, and this should allow you to do a normal start. A better way to do this would be to put a fuel pressure gauge on it, start the car to confirm pressure, and then let it sit overnight. If when you come back it's at 0, then that indicates that you have some sort of internalleak in the fueling system (my Suburban exhibits this exact behavior), which is probably either a fuel pump or a pressure regulator, can also sometimes be a leaking injector.

One clue here, does the car make full power? Sometimes when one of these fuel components is dying and not holding pressure while the car is off, it can also not provide proper pressure, especially at high RPMs and high load and thus result in reduced power.

Hope this helps you some. I'm not a Cadillac mechanic (and am on the road to getting a DeVille), but I spent several years as a Jaguar mechanic and have done my own work on all the cars I've owned, so these are some basic tips that I would convey.

 

Fordcrusher (in this thread) and Katz ( in General tech area) have posted great info on batteries and related problems. I know 'Stealth is up on this too. Maybe we can combine this stuff to the general tech area or a battery and related thread area. Would not want to see the info here lost under other posts.

G.A.R.Y.

 

Very good suggestion G.A.R.Y. , How is this accomplished? Cut and paste or re-posts?

I suppose being from the Great White North gives us special insight into battery issues, especially in the winter. I look at battery connections, cleaning and replacement as a preventative maintenace items, 3 or 4 years and replace even if it is still starting your car. I am sure many Northern State members do the same thing. Even here in Toronto it is -13 today.

I carry a set of 18 foot 1 guage jumper cables in my GMC, and a set of 10 foot 4 guage in the Deville, both with strong clean copper clamps. At this time of year they get weekly use in helping other motorists.

 

Thanks, G.A.R.Y., I try to share what I know.

I live out here in semi-rural Pennsylvania. Normal temps here right now are about 10-20F. Before that I lived in Indiana and New York City, and battery issues at low tempswere still definitely common.My fiancee's Range Rover had a newish 600CCA battery from WalMart which died recently. I put in a 900CCA quality battery and it works great. My philosophy is youalways want to be the one giving others a jump, not vice versa!If you want to put in a sticky/tech section or something I'd be glad to write something a bit more formal for that.

I have a set of 10 foot 4 gauge cables that I carry in whatever vehicle I'm driving. The only time they've failed to start a vehicle right up has been on an F-550 with a 7.3L PowerStroke diesel. Every other vehicle has started right up as if it's using its own battery.