'95 E320 Won't Start
 

Hi guys this car has been driven maybe 600 miles in the last 2 years (79K total miles). I try to go start it every couple weeks and run it when the weather is nice.

Wiring harness replaced about a month ago. At that time, no check engine light and the car was running perfectly. The car got new plugs and wire connectors at that time. After changing the harness, I drove for about 75 miles with no problems whatsoever. Also, I topped off the tank to full with premium fuel.

Today I go to start it and it cranks with full power, just won't start. Where should I start?

Thx,

-GH

Search "OVP relay" ..

Is the weather hot where you are?

These cars are susceptible to heat-related electrical gremlins when the temperature gets really hot for more than one or two days.

I installed a new neutral safety switch about two months ago and, after 2 days of near-100 degree temperatures, the car does not start in the morning unless I nudge the shifter a bit. (The switch was misaligned, but useable, and I am guessing heat-related expansion (or loosening) of the shifter linkage, mounting bolts, or some other connected component has misaligned it further.)

About two years ago, under similar hot weather conditions, the ABS pump started running and would not stop – even when the car was powered off. After a short drive, it stopped and the problem never recurred.

NSS is Starter Lock-out..
His car CRANKS...
so.... He has no spark or gas ..OVP will effect both..if OVP is OK , next step is Fuel Pressure test.

I know. I was commenting on the possible heat connection to what will likely turn out to be an electrical issue.

I see...
His first check should be the OVP , and we all know why that is the First Suspect on that chassis.
I suspect OVP failure if the tires look soft....:)

Thanks for the replies gentlemen. I tried tapping the OVP today, and also inspected the OVP fuse to no avail.

BUT, I noticed something today I didn't last evening. The fuel pump(s) do NOT kick on when the car's ignition switch is powered up. No noise other than the usual dash buzzers. I will search this problem unless someone else has had this symptom and has possible solutions.

Thanks,

-GH

Check the fuse on top of the fuel pump relay


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Arthur, I looked @ this fuse and it appeared normal. Should I try a new relay? Perhaps there is someway to test if the relay is getting power? Do these relay's fail with some regularity?

Thx,

-GH

Pull the relay and jumper pins 30 and 87 where the relay plugs in.
That should run the pumps when the key is on.
That jumper will verify pumps.
The relay 12 v. signal from the ECU can be checked with a test lamp/meter at pins 85/86 of relay plug. If no 12v sig , then ECU is not sending power to relay [ which is why I suggested OVP].., but you can also check the fuse box [ spin all the fuses in their holders ..when a car sits , they loose contact in the holders].....

Ok Arthur, I went up to see the car again today and here's what we know.

When the pins were jumped (30 & 87) the fuel pumps light up, the key didn't even need to be on.

When I put my voltmeter @ 85 & 86 I get a reading of .80 volts. Voltmeter was set to 20 VDC...

So, it looks like I'm ordering a OVP...

Thanks,

-GH

<When I put my voltmeter @ 85 & 86 I get a reading of .80 volts. Voltmeter was set to 20 VDC...

>
..with the key ON??

..with the key ON??

Yes, sorry the key was on when I did the voltage reading. Also, I pulled the ovp and I see ovp plug 30a and 87E appear to be darker like they saw heat. Also inspecting the ovp I see 2 heat marks around the lip of the fuse door.

I have the old ovp # 000 540 52 45

Thx!

-GH

<I have the old ovp # 000 540 52 45>

OK ..have to change it regardless.

Arthur, OVP installed tonight (it just arrived UPS today). Car started right up with no problems. Running great once again.

I very much appreciate the help. I was doubting the OVP initially since I didn't hear the fuel pumps coming on. But, that was because I didn't understand virtually everything important to making the car start goes through the OVP.

Thanks,

-Grant