Car Starting Issue/Question

[lazabby]

A couple of days ago I backed my car out of the garage in order to do some things in the garage. When I got back in the car to move it back into the garage it wouldn't start. The engine turned quickly as if it had power but wouldn't start. I have an EFI engine with a fuel pressure gauge and the gauge indicated plenty of fuel pressure.

I decided to put the battery on a trickle charge even though the engine was cranking fine. I charged the battery overnight and during the next day. When I got home yesterday evening I checked all the fuses. All fuses looked good. Check the fuel kill switch in the driver side footwell. That looked good. Checked the wire going from the coil to the distributor. It seemed secure but pushed it down just to be safe. Checked the ground wire from the EFI system that is bolted to the engine. A little loose but secure.

I hooked up the battery. At first the engine turned fast and started briefly but died. If I had been faster I could have given it gas and it would have stayed running. When I turned the key to start it again, the engine turned noticibly slower. After several tries I got it started so I moved it back into the garage.

Any ideas? Battery going bad? It's 2-3 years old and has been drained and charged multiple times. One friend thinks it's the battery. I'm mystified though why the engine would turn string but not start if it's the battery.

Shannon

[David T]

A couple of days ago I backed my car out of the garage in order to do some things in the garage. When I got back in the car to move it back into the garage it wouldn't start. The engine turned quickly as if it had power but wouldn't start. I have an EFI engine with a fuel pressure gauge and the gauge indicated plenty of fuel pressure.

I decided to put the battery on a trickle charge even though the engine was cranking fine. I charged the battery overnight and during the next day. When I got home yesterday evening I checked all the fuses. All fuses looked good. Check the fuel kill switch in the driver side footwell. That looked good. Checked the wire going from the coil to the distributor. It seemed secure but pushed it down just to be safe. Checked the ground wire from the EFI system that is bolted to the engine. A little loose but secure.

I hooked up the battery. At first the engine turned fast and started briefly but died. If I had been faster I could have given it gas and it would have stayed running. When I turned the key to start it again, the engine turned noticibly slower. After several tries I got it started so I moved it back into the garage.

Any ideas? Battery going bad? It's 2-3 years old and has been drained and charged multiple times. One friend thinks it's the battery. I'm mystified though why the engine would turn string but not start if it's the battery.

Shannon

Can't help a lot since you have a non-standard set-up. It is possible when the battery gets weak the EFI doesn't have enough voltage to work so you don't get any spark. Could be a wiring problem or a bad battery. Could be some kind of malfunction or programing error with the EFI. You need to get someone who knows how to trouble-shoot your EFI system.

[lazabby]

Actually the EFI is running okay. It just didn't make sense that the car would start fine and then 20 minutes later not start. I'm betting on the battery at the point.

[Exolis]

Do you have a voltmeter? If so, with the car off (best to disconnect and wait 3hrs or more from last time the engine ran), read the voltage. If it's 12V or above, it should be good. Also measure the voltage when the vehicle is running, should be 13V or higher(Ideally 14V-14.5V).

When you say it started briefly, but died. Is that meaning it started firing then gave out? Also, when you say you started it then 20 minutes it didn't, that makes it sound like Alternator problem, unless the battery is bad enough not to hold any kind of charge, but the fact you were able to start it with no mention of jumping says the battery was good enough to get it started, alternator wasn't recharging and the battery didn't have enough power to start again.

[lazabby]

When you say it started briefly, but died. Is that meaning it started firing then gave out? Also, when you say you started it then 20 minutes it didn't, that makes it sound like Alternator problem, unless the battery is bad enough not to hold any kind of charge, but the fact you were able to start it with no mention of jumping says the battery was good enough to get it started, alternator wasn't recharging and the battery didn't have enough power to start again.

When I backed the car out of the garage the car only ran for about 20 seconds when I turned it off. The had started fine. That wasn't much time for the alternator to charge the battery. When I went back later to start the car it sounded as if the battery had a full charge but the car wouldn't start. That's when I went ahead and put the battery on a charger over night. The next day after the overnight charge the engine turned over normally and the car started briefly but i didn't give it the gas to continue firing and it died. It was a cold engine so it needed a little help. It took several more tries to get the car started and the engine was slower in turning over when I was trying to start it.

Good idea about putting the volt meter on it to see if it's holding a charge.

Shannon

[DrJeff]

Could it be wiring to the starter motor? Could the process of cranking the engine be disturbing a loose connection?

[lazabby]

Could it be wiring to the starter motor? Could the process of cranking the engine be disturbing a loose connection?

That's a good place to look. It doesn't hurt to check for any loose connections. Thanks.

[lazabby]

I'm still having an issue with starting. Tonight (after sitting for about three weeks) I tried starting the car. The engine turns quickly but won't catch. I took the battery out and took it to the local parts store for a battery test. They said it was 45% charged. This is a Sears Diehard B-16 with 770 CCA. It seems that would be enough to start the car, wouldn't it? Recently the car does seem to start better with a full charge but it seems to me that the battery doesn't need to be 100% charged in order to start the car.

I suspect that there is something in the car draining the battery so I need to check that out.

What could be done to help an easier start? Cleaning grounds, etc? It wasn't that long ago that I cleaned all grounds that I could locate. I recently checked all fuses for corrosion.

[hmcelraft]

If you still have the OEM spark setup, I would address the high voltage start relay circuit (see page 24, etal of the technical manual). That is the circuit that throws the extra voltage to the coil during start. I've had issues with dirty connections on the resistor - and relay function, too (the relay mounted to the firewall that provides the higher electrical to the resistor - also the one that does not appear in any wire diagrams).

I would think that a 770 CCA battery is marginal on the DeLorean. I believe a 1,000 CCA battery would be more appropriate. Also, if you do not have a master on/off switch for the battery, 3 weeks is going to be a big drain. A 1,000+ amp marine battery switch works great and they are not that expensive. I really do not like battery tenders on vented lead acid batteries - especially given the location of the DeLorean battery below the fuse/relay compartment. I use an Optima battery to eliminate any possibility of vapors.

It does sound like your issue is electrical to me.

One more thing I would suggest as a spark test - given the symptoms you have mentioned - would be to connect a jumper wire from the positive battery post in the engine compartment directly to the coil wire on the resistor to see if you get a quicker start. Don't leave the jumper wire on that post very long (only a few seconds) or you may damage the coil, especially if it starts and the alternator kicks in. You're only looking for the start - not the run. You can leave the jumper on the "start" post of the resistor for a longer time after the engine starts - but, not more than a minute or two at a time.

[dn010]

If you are using any crank/cam position sensors, replace them and see what happens.

[David T]

If you are using any crank/cam position sensors, replace them and see what happens.


Any information we can provide is going to be very unreliable because your car has been modified. If it is a crank or cam sensor it shouldn't start at all. Your best bet is to find the shop that did the conversion or is at least familiar with your EFI system so they can trouble-shoot it. It is possible it is a fuel problem so that can't be ruled out yet. BTW, how much fuel do you have?

[Gary]

You said you had fuel pressure but are your injectors plugged? Squirt a little gas into the air metering plate just to be sure. Something may have become dislodged and ended up in the system. The K-jet is very sensitive to things like that.

Gary

[Gary]

Opps!you have an EFI. Still, is there a way you can see if you are getting gas to the pistons

Gary

[skill]

Lazabby, I have the same battery, a Diehard. I have been dealing with the same problem for the last week... I troubleshot everything; even called Danny at DMC Calif last night who helped me out (Thanks D!)... The culprit was the Diehard battery, under power and insufficient to light up my car. I temporarily switched my battery for a higher powered one and it fired up... so tomorrow, I'll be taking it back to Sears and replacing it! Double~triple check your voltage on your battery (w/a voltmeter) ... that may be it!

[lazabby]

Lazabby, I have the same battery, a Diehard. I have been dealing with the same problem for the last week... I troubleshot everything; even called Danny at DMC Calif last night who helped me out (Thanks D!)... The culprit was the Diehard battery, under power and insufficient to light up my car. I temporarily switched my battery for a higher powered one and it fired up... so tomorrow, I'll be taking it back to Sears and replacing it! Double~triple check your voltage on your battery (w/a voltmeter) ... that may be it!

Perhaps it is the battery. I was able to get it started but it took a while. Drove it around with no problems. The voltage per the volt meter was 12.7. But with 770 CCA perhaps it needs a battery with higher CCA.

[lazabby]

Opps!you have an EFI. Still, is there a way you can see if you are getting gas to the pistons

Gary

I have a fuel pressure guage on the engine and it's showing plenty of fuel pressure. The problem seems to be a weak battery under the influence of cold (50 degrees) weather or perhaps a weak link in the electrical system.

[lazabby]

Any information we can provide is going to be very unreliable because your car has been modified. If it is a crank or cam sensor it shouldn't start at all. Your best bet is to find the shop that did the conversion or is at least familiar with your EFI system so they can trouble-shoot it. It is possible it is a fuel problem so that can't be ruled out yet. BTW, how much fuel do you have?

Fuel is good. I think I have over 1/2 a tank. No crank or cam sensor.

[David T]

Perhaps it is the battery. I was able to get it started but it took a while. Drove it around with no problems. The voltage per the volt meter was 12.7. But with 770 CCA perhaps it needs a battery with higher CCA.

One possibility is the EFI is sensitive to voltage and when you are starting the motor the voltage drops too much for it. A lot has to do with how the EFI is wired and if any connections are loose or dirty. If the battery is able to crank the motor it should be big enough, getting a bigger battery is only going to cover the symptom, not fix the problem. When the motor is running you should see more than 12.7 volts.

[lazabby]

One possibility is the EFI is sensitive to voltage and when you are starting the motor the voltage drops too much for it. A lot has to do with how the EFI is wired and if any connections are loose or dirty. If the battery is able to crank the motor it should be big enough, getting a bigger battery is only going to cover the symptom, not fix the problem. When the motor is running you should see more than 12.7 volts.

The 12.7 volts was before the engine started. I didn't check it with a voltmeter when it was running.

All connections appear to be in good shape but I was thinking about cleaning all the fuses, connections and grounds anyway just to be on the safe side.