- Joined
- Jan 20, 2022
- Messages
- 1,518
- Reaction score
- 2,465
- Location
- Homer Glen, Il
- My Car
- 1971 Mustang Mach 1 351c M-code FMX trans and 9 inch rear end
As I mentioned in my build thread, I drove the Mustang home from the body shop last Saturday. It was it's maiden voyage and overall it went well, but a few issues arose in the 25 mile drive.
I have not been able to have a chance to look at anything all week and I am planning on looking at it tomorrow morning for the first time. I thought I would reach out for a little guidance before I jump in blindly to try and start diagnosing.
First off, the tach stopped working while it was at the body shop. Rocketman converted the tach to a current three wire style and also converted the Alt gauge at the same time. While he had the three gauge cluster, he tested the oil and temp gauge and said they were working. Midlife wired the harness for those alterations at the same time as he went through all of my harnesses, so I think that they shouldn't be the problem, right?
All of the gauges including the tach performed properly when I first got the new engine in the car and got it started. They all worked for the first few around the block test drives The car was towed to the body shop and we only drove it across the parking lot from building to building as necessary. Although the car only had about a mile on the odometer since it was started the engine has been started and ran a few times and the tach always worked. It continued working when we would drive the car back and forth from the body shop building to the paint building while we were painting the car. One day I started the car at the body shop to move it and the tach didn't move, I couldn't think of us doing anything under the hood that might have disrupted anything at the time. I am looking for ideas on how to test to find the failure causing this.
The other issues started on the ride home, first was the speedo stopped working about halfway home. The odometer show I got about 14 miles before is stopped registering. I am hoping that is just the cable wasn't pushed all the way in and clipped on the back of the speedo head.
The other issue I need guidance on is, how to properly diagnose the temp gauge. The temp gauge worked perfectly almost the whole 25 mile drive home. About a block from my house the temp gauge dropped like someone switched it off. The fuel gauge, battery gauge, and and oil pressure gauge are all working so I think that rules out the relay on the back of the speedo cluster, right? Also, the temp sensor is brand new, I know new doesn't mean it's any good but that shouldn't be the problem, right?
Any assistance or guidance I can get on how and what I should start testing to diagnose these issues is much appreciated. I am not a technician by any means, I am good at disassembling and reassembling but actually diagnosing a problem, I am not awesome at. I am hoping I can get led in the right direction and I can determine the causes and resolve these issues.
I have not been able to have a chance to look at anything all week and I am planning on looking at it tomorrow morning for the first time. I thought I would reach out for a little guidance before I jump in blindly to try and start diagnosing.
First off, the tach stopped working while it was at the body shop. Rocketman converted the tach to a current three wire style and also converted the Alt gauge at the same time. While he had the three gauge cluster, he tested the oil and temp gauge and said they were working. Midlife wired the harness for those alterations at the same time as he went through all of my harnesses, so I think that they shouldn't be the problem, right?
All of the gauges including the tach performed properly when I first got the new engine in the car and got it started. They all worked for the first few around the block test drives The car was towed to the body shop and we only drove it across the parking lot from building to building as necessary. Although the car only had about a mile on the odometer since it was started the engine has been started and ran a few times and the tach always worked. It continued working when we would drive the car back and forth from the body shop building to the paint building while we were painting the car. One day I started the car at the body shop to move it and the tach didn't move, I couldn't think of us doing anything under the hood that might have disrupted anything at the time. I am looking for ideas on how to test to find the failure causing this.
The other issues started on the ride home, first was the speedo stopped working about halfway home. The odometer show I got about 14 miles before is stopped registering. I am hoping that is just the cable wasn't pushed all the way in and clipped on the back of the speedo head.
The other issue I need guidance on is, how to properly diagnose the temp gauge. The temp gauge worked perfectly almost the whole 25 mile drive home. About a block from my house the temp gauge dropped like someone switched it off. The fuel gauge, battery gauge, and and oil pressure gauge are all working so I think that rules out the relay on the back of the speedo cluster, right? Also, the temp sensor is brand new, I know new doesn't mean it's any good but that shouldn't be the problem, right?
Any assistance or guidance I can get on how and what I should start testing to diagnose these issues is much appreciated. I am not a technician by any means, I am good at disassembling and reassembling but actually diagnosing a problem, I am not awesome at. I am hoping I can get led in the right direction and I can determine the causes and resolve these issues.
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