Another No-Start 3.2 , but....

[Tcannon88]

Hopefully a little different.

Engine won't crank. But, I can hear the fuel pump when ignition is in start position. Replaced DME relay, checked fuel pump fuse anyway. Replaced reference sensor (with Bosch replacement).

Still no crank. But, engine cranks every time with jump start. So....replace 2 year old Red Top Optima, still only cranks with jump start. Occasionally (one in 20), it will crank and start without jump.

Not sure where to go from here....

88 3.2 Targa. Driven about 5-6k miles per year. When engine was out two years for clutch, replaced CHT, reference and speed sensors.

Any ideas?

[Justin@Athens]

Bad ground (check transmission ground strap and the ground to frame in the trunk area)

or bad positive lead cable connection at the point of contact with battery or on the starter end

[Drisump]

I think Justin is right on track but I'm wondering if it's more pedestrian than that, the jumper cable would would connect to the positive lead going directly to the starter, I'm wondering if the battery connection on the positive is not what it should be. You changed out the battery right? Presumably you cleaned the clamp and made sure the connection was good as possible. When you're jumping, are you grounding to the NEG on the battery or going to the body? If you're going to the battery, the connection must be fine but if you're going to the body, the ground straps or the quality of their connections may not be sufficient. I'm thinking that it's likely the body end of the ground strap coming off the battery. Cheers

[Tcannon88]

When I changed the battery, I did inspect the cables and connections at the battery. The positive seems to be in very good condition, at the battery end. I replaced the negative two years ago, and it seems to be in great shape. When I jumped the car, I connected both jumper cables to the battery. I will inspect the connection at the starter and the body connection of the negative cable, as well as the system grounds.

Thank you both for the suggestions.

[Tcannon88]

Sooo..... I checked all of the ground points. Fuse box ground, Battery ground, ground at fuel filler, engine/ transmission/ body ground at trans mount, fuel filter ground, and ground on number one intake runner. By check, I mean I visually checked each one, and manually tested it to make sure it tight. I took extra care with the batter ground, disconnecting it at the body and making sure there was a good connection. It appeared to be very good and the cable seems to be in great shape. The starter connection is not as easy. This requires a trans drop. So, I checked the connections at the ignition switch. That connector seems to be on tight.

Any more ideas?

[Drisump]

I think, given your symptoms, you are receiving insufficient "jam" from the battery without booster cables being applied. If you are connecting the cables to the two clamps, the only thing you are potentially bypassing is the actual connection to the battery that is in the car. I can't think of anything else given the info....sorry buddy, but are you sure that the terminals and clamps are clean and tightly connected? Good luck

[jjeffries]

Ignition switch?

[S ECU Repair]

Try this specially the Voltage and ground inputs in your DME .

[Joe Bob]

If all else fails.....try tapping the solenoid on the starter. Typical issue with older Bosch starters.

BTW, do you hear a click at the starter when attempting to crank the engine?

Other than replacing the starter, some have opted for the "Hot Start" kit. Essentially a relay wired into the starter that gives it a higher jolt.

[Tcannon88]

The starter/ solenoid looks to be a pain to get to. The Bentley manual recommends dropping the trans to get it. Hope that is not my issue! Where would I get a "Hot Start Kit'? I would rather get back to spec, but would consider this in the short term.

With regard to the DME harness tests, I assume these are performed with the DME unplugged, measuring desired results at the appropriate pins on the DME connector?

Thanks, again, for all the suggestions.

[Joe Bob]

I was just under the SC doing heater stuff. With the heater tubes outta the way, easy.

Remote Starter Solenoid Instructions

Don't let the "Ford" part scare you. Common useage on 911 and 914s....

[ischmitz]

If the fuel pump comes on this indicates a good ignition switch, DME relay, etc. My first guess would be the yellow wire came loose at the starter solenoid. This wire makes the starter solenoid close the circuit for the stater motor.

If you want to diagnose, find that yellow wire at the starter solenoid and make sure +12V appear when you crank. If not the plug on the rear relay panel could be loose. If yes, it's either a bad or stuck soleniod. If the soleniod engages (you can hear that) and still no crank it's the starter motor.

Ingo

[Wil Ferch]

Haven't read thru all the posts....but started to get a feeling the main positive cable connected to the battery may be the culprit. I had a problem in a "no-start" condition where the two battery posts were clean and tight.... BUT....when I jiggled the positive cable aggressively near the battery connection ( car "off" prior to start attempt)...and then tried to start...it worked! Obviously, severely jiggling the cable prior to start changed something.

Further investigation revealed that the stranded copper wires disappearing under the insulation sheath of the positive cable....showed a bit of green corrosion.

After disconnecting both the neg and positive cables to the battery ( safety first)..... Started cutting back the insulation on the main positive cable, and to my horror saw about a 6" run of very green copper cable. I cut off the positive battery clamp, cut back the insulation.....cleaned the strands the best I could, added conductivity-enhancing grease to the strands ( Burndy Penetrox)....retaped the insulation and re-attached a new positive battery clamp to the now-clean wires...and buttoned everything back up. Also, I never had a severe overcharge condition that caused battery acid spillage ( battery tray was still perfect)...I could only imagine the cause was due to normal "venting" of the battery causing a local bad corrosive atmosphere for the cables. I replaced the normal battery with an Optima ( non-venting)....and the Optima install requires a longer negative battery cable, so I replaced the grungy looking neg cable too.

Worked fine without issue thereafter.