Erratic Oil Pressure Gage

Jeff:

Hopefully I don't sound inept. But after 35 years of 1967 GT 350 Ownership ( despite owning my SVO & TC during much of that time) I am just now having to deal with the "1980's Ford Electronic Age" in terms of Maint and repair.

Which is also ironic in that 90% of my business is in Advanced Fuel System development ( where I am no stranger to PWM control in our Diesel Fuel injection project) where I manage teams of Techs and Engineers. So now my Non-Business Electronics knowledge will finally become part of my enthusiast life.

This AM as I was driving to refuel , my Left signal Dash indicator light has stopped working !
Signal Lamps both rear and Front are working properly - ANOTHER electrical gremlin has popped it's head up.

Since I have never had this happen on the TC - Is it a pull the Inst Cluster and Fix or am I looking at a more involved issue ??

Not starting out to be my week.

Later:

E. J.

I would guess either the bulb burned out or there is a connection problem with one of the plugs on the back of the cluster that plugs into the printed circuit. Either way, pull the cluster. Pretty easy.... takes 10 minutes after you have done it a few times. Many, if not all, bulbs are likely original. I would replace all the bulbs when you have it out. #194. The firm ride light is a LED.

Jeff:

Thank you and understood -

Believe it or not two hours after I posted - I was picking up my wife and Bingo !!

I look down and the Left Turn Light in the cluster is NOW working Again - Has worked for the last 36 hours without missing a beat.

I will take the cluster out and replace bulbs in any event - Just seems smart thing to do .

Also Cleaned off OP Sensor Connector inside little cover and Connection point on Sensor itself - Reading is SLIGHTLY less erratic - But not where it should be consistently - Di-electric grease will come after Resistor test

I will run resistor test Friday AM
If that does not indicate bad sensor

I will change Oil & Filter as planned.

If I STILL have a Pressure problem - It is likely I will be looking at the Oil Pump Pick-Up as a potential issue. Not looking forward to that possibility.

Sincere thanks for all your advice and insight -

Later:

E. J.

I dont really trust the stock OP, temp, fuel gauges on any car, especially an 24 year old Ford. What I did was T into the OP sender fitting and permanently install a mechanical OP gauge under the hood so if the dash gauge acts weird, I can just pop the hood and see what the actual pressure is. Did the same for coolant temp... put a mechanical gauge under the hood so I can see exactly what the water temp is if I have a reason to not trust the dash gauge. I put these 2 gauges under the hood because I didnt have any room inside the car... Too many aftermarket gauges already to monitor other functions!

Example: A few years back, OP gauge in dash was reading low, near the red at idle with oil at operating temp = seriously worried. Popped hood, and mechanical gauge showed showed 25-30 psi at idle and went to 45-50 when revved. Traced the problem to the push on connector on the OP sender was a little loose.

Jeff:

Understood - As indicated I gave the OP Sensor Connector a little Clean- Up ( Quickie ) not my usual Over the top Electrical Contsct job - But I was doing a "rush" trouble shoot .

FYI - I have seriously considered the "Under hood" External Gauge option. Ran an under hood OP gauge on the 427 Fairlaine SS/C I raced in 1966-67. Made work easier.

Had planned to work on the TC yesterday and today - But something called Work - Took preference. Two Projects I am involved with had HUGE problems at the same time in two different parts of the country - Go Figure - Automotive development projects with Problems ???

So the TC Sits in the garage until late Sat earliest possible opportunity based on where things stand work wise now.

As soon as I get in the shop and track ( hopefully) down teh OP issue . I will post my findings.

Thanks again Jeff.

Later:

E. J.

Jeff:

Changed Oil (5-w30 Syntek ) and Filter ( FL-300 ) over the weekend.

No Joy -

OP Pressure Gauge reading STILL all over the place -

Had not expected an improvement - Still believe it is electrical IVR as you have thought.

Have IVR and will be installing this weekend.

Will update as to results.

Later:

E.J.