Forum Replies Created
-
Replies
-
I have an old Chevy 77 c60 dump truck with drums all around. My brake booster went out. My ? is i been driving with the bad booster can it cause to make the wheel cylders leak?
No. The wheel cylinder will still receive the same amount of hydraulic braking pressure regardless of the driver getting assistance from the brake booster.
Cool to see a big truck with something other than s-cam style brakes… I’ve never seen them before myself, but always heard about it. If you wouldn’t mind, it’d be cool to see pics (or video) of this brake job. :side:
I have an old Chevy 77 c60 dump truck with drums all around. My brake booster went out. My ? is i been driving with the bad booster can it cause to make the wheel cylders leak?
No. The wheel cylinder will still receive the same amount of hydraulic braking pressure regardless of the driver getting assistance from the brake booster.
Cool to see a big truck with something other than s-cam style brakes… I’ve never seen them before myself, but always heard about it. If you wouldn’t mind, it’d be cool to see pics (or video) of this brake job. :side:
Give me the year/make/model of the vehicle with the steering problem and I will attempt to get you a diagnostic procedure specific to the vehicle.
Give me the year/make/model of the vehicle with the steering problem and I will attempt to get you a diagnostic procedure specific to the vehicle.
was engine data monitored while the engine was put under acceleration? Is the computer actually ‘seeing’ what it needs to see?
Any one of these can affect driveability; it is possible the ECM may not be commanding an advance in timing because it thinks it’s at idle (when it’s actually not:)
- Fuel injector Pulse Width
- Engine Coolant Temperature
- Engine RPM
- MAP or MAF sensor
- Intake Air Temperature
- Throttle Position
- O2 Sensor
- Short Term/Long Term Fuel Trim
Additionally, you may be able to monitor ‘timing advance’ specifically as you accelerate the engine and see if that is actually the problem.
Here is one related Technical Service Bulletin:
ENGINE – TIMING BELT – S/M REV
TSBID: 8267 Mfg Num: 18-46-98 Issue Date: 1998-04-24If you have a distributor, it’s possible that one of the components, such as the magnetic pickup, centrifugal advance, or Ignition Control Module might be the issue.
was engine data monitored while the engine was put under acceleration? Is the computer actually ‘seeing’ what it needs to see?
Any one of these can affect driveability; it is possible the ECM may not be commanding an advance in timing because it thinks it’s at idle (when it’s actually not:)
- Fuel injector Pulse Width
- Engine Coolant Temperature
- Engine RPM
- MAP or MAF sensor
- Intake Air Temperature
- Throttle Position
- O2 Sensor
- Short Term/Long Term Fuel Trim
Additionally, you may be able to monitor ‘timing advance’ specifically as you accelerate the engine and see if that is actually the problem.
Here is one related Technical Service Bulletin:
ENGINE – TIMING BELT – S/M REV
TSBID: 8267 Mfg Num: 18-46-98 Issue Date: 1998-04-24If you have a distributor, it’s possible that one of the components, such as the magnetic pickup, centrifugal advance, or Ignition Control Module might be the issue.
Seems to be a ECM type of issue… any codes?
If no codes, I would lean more towards a mechanical issue.
Seems to be a ECM type of issue… any codes?
If no codes, I would lean more towards a mechanical issue.
Let’s unravel some of the mystery…
To be honest, I am kinda overwhelmed here… there is a lot going on with a lot of resisters and amplifiers and what not.
Well.. to test this sensor, this is probably what I’d do:
- Pull the senor.
- Ohm test the sensor in the ‘home’ position. Compare to expected reading.
- Ohm test the sensor in ‘fully actuated’ position. Compare to expected reading.
- Make sure it is getting the correct 8 volt input. (wierd.)
- Apply the 8 volt reference to the sensor.
- If input is good, check the outputs:
- Check the sensor at the ‘home’ position and see if you get expected voltage.
- Check the sensor at the ‘fully actuated’ position and see if you get expected voltage.
- Ground circuit resistance should be below 10mV (ASE standard for sensors)
- Pull a known good sensor and compare the above results vs. the faulty sensor.
[li]If possible, swap a bad sensor with a good sensor and see if the problem (or codes) follows the suspected bad sensor. If not, the problem may be somewhere in the affected circuit.
This is all just basic sensor circuit diagnosis… just to see if you can identify any problem area(s).
Of course, let’s not overlook the basics; here is just what one person said who had a similar problem:
I found that on both sides the small connecting rod was attached to the lower control arm but was dangling loose and not inserted into the boot on the level sensor unit arm. How they both came out is a mystery although my son did have to call AAA for a flat tire change this summer and they may have lifted the car in a way that dropped the front wheels enough to pull the arms out of the rubber boots. That is about the time that he first saw the service suspension message. (My son had the car this summer for his college internship and he is not mechanically inclined!) I reinserted both rods and cleared the trouble codes. The service suspension system message is now cleared and no trouble codes reappeared.
Let’s unravel some of the mystery…
To be honest, I am kinda overwhelmed here… there is a lot going on with a lot of resisters and amplifiers and what not.
Well.. to test this sensor, this is probably what I’d do:
- Pull the senor.
- Ohm test the sensor in the ‘home’ position. Compare to expected reading.
- Ohm test the sensor in ‘fully actuated’ position. Compare to expected reading.
- Make sure it is getting the correct 8 volt input. (wierd.)
- Apply the 8 volt reference to the sensor.
- If input is good, check the outputs:
- Check the sensor at the ‘home’ position and see if you get expected voltage.
- Check the sensor at the ‘fully actuated’ position and see if you get expected voltage.
- Ground circuit resistance should be below 10mV (ASE standard for sensors)
- Pull a known good sensor and compare the above results vs. the faulty sensor.
[li]If possible, swap a bad sensor with a good sensor and see if the problem (or codes) follows the suspected bad sensor. If not, the problem may be somewhere in the affected circuit.
This is all just basic sensor circuit diagnosis… just to see if you can identify any problem area(s).
Of course, let’s not overlook the basics; here is just what one person said who had a similar problem:
I found that on both sides the small connecting rod was attached to the lower control arm but was dangling loose and not inserted into the boot on the level sensor unit arm. How they both came out is a mystery although my son did have to call AAA for a flat tire change this summer and they may have lifted the car in a way that dropped the front wheels enough to pull the arms out of the rubber boots. That is about the time that he first saw the service suspension message. (My son had the car this summer for his college internship and he is not mechanically inclined!) I reinserted both rods and cleared the trouble codes. The service suspension system message is now cleared and no trouble codes reappeared.
