Alchemy333 Posted December 30, 2022 Share Posted December 30, 2022 Recently, I purchased a 90 Reatta Coupe as a project. Starts up and runs great 109k mi. Brake pedal is hard and both lights are on. The motor runs continuously. Changed the fluid, checked all connections... did alot of research on forums. Trouble finding these exact symptoms. Found a used (tested) booster on ebay ($340) and swapped it out... same problem. I figure if it were a bleeding issue (which i havent addressed)at the calipers, it'd still build preassure and stop running. What am I missing. Could both accumulators be toast? Is there a bleed at the booster? Relay?🤷♂️ Thanx in advance! Link to comment Share on other sites More sharing options...
Ronnie Posted December 30, 2022 Share Posted December 30, 2022 13 hours ago, Alchemy333 said: Found a used (tested) booster on ebay ($340) and swapped it out... same problem. I figure if it were a bleeding issue (which i havent addressed)at the calipers, it'd still build preassure and stop running. What am I missing. Could both accumulators be toast? Is there a bleed at the booster? Relay?🤷♂️ The hard pedal and red warning light are telling you there is no pressure in the system - usually caused by the pump not running. If the pump is running continuously the relay isn't the problem and the accumulator won't prevent the pump from building pressure even if it is bad. Once all the fluid is drained out of the pump it can be really hard to get the air out. Here are instructions for getting the air out. -> How To Purge Air From The Brake Pump If the instructions don't work for you, you might have to rig up a hand vacuum pump to connect to where the steel pressure line connects, then suck the air out of the pump. Also, check to make sure fluid is getting to the pump through the line coming from the reservoir. 1 1 1 Link to comment Share on other sites More sharing options...
Alchemy333 Posted December 30, 2022 Topic Author Share Posted December 30, 2022 11 hours ago, Ronnie said: The hard pedal and red warning light are telling you there is no pressure in the system - usually caused by the pump not running. If the pump is running continuously the relay isn't the problem and the accumulator won't prevent the pump from building pressure even if it is bad. Once all the fluid is drained out of the pump it can be really hard to get the air out. Here are instructions for getting the air out. -> How To Purge Air From The Brake Pump If the instructions don't work for you, you might have to rig up a hand vacuum pump to connect to where the steel pressure line connects, then suck the air out of the pump. Also, check to make sure fluid is getting to the pump through the line coming from the reservoir. That makes sense. I tried loosening the high pressure line, and got nothing. Thought about loosening the accumulator too... but, wasn't sure what I was doing. I'll report back with results. Thanx Link to comment Share on other sites More sharing options...
Padgett Posted December 30, 2022 Share Posted December 30, 2022 If relief is open, pump will run but not build pressure. Or the pump itself be bad but the motor good. 1 Link to comment Share on other sites More sharing options...
2seater Posted December 30, 2022 Share Posted December 30, 2022 The pump itself is generally reliable as long as it remains full of fluid. There are no actual seals on the inside of the pump except two small semi-flexible cups inside the rotor that act as the pump. The pump is a piston pump that spins very rapidly inside an eccentric housing with a ball bearing running against the inside of the housing which moves the piston cup to pump the fluid. It is a very poor air pump and it needs the weight of the fluid to help flinge the pistons outwards in their bore to press against the eccentric. In other words, they may get stuck if the pump is dry, but applying vacuum to the outlet may help if the standard bleeding operation doesn't work. The pump is high pressure but low flow. It can take upwards of a minute or more to fill a good accumulator from empty to 2600psi cut out pressure. The standard accumulator only holds 1/4 liter so the pump only produces about 250cc/min, or about 8.5 fl/oz. 2 1 Link to comment Share on other sites More sharing options...
Alchemy333 Posted December 31, 2022 Topic Author Share Posted December 31, 2022 Took a bit of coercing... but, got the pump bled and holding preassure. Bled the lines... and got brakes. Still feels a bit spongy though... and the ABS light is still on. Brake warning light is off. Bolt broke off at the mount too, so... gonna have to pull the whole unit to drill out and replace at some point as well😅I had it supported while loosening the accumulator. But, it was lock-tight on.🤦♂️zip tied for the moment. 3 Link to comment Share on other sites More sharing options...
Alchemy333 Posted January 1, 2023 Topic Author Share Posted January 1, 2023 Feeling kickback at the pedal. I feel mostlikely a wheel speed sensor. I did notice some cracks in one of the lines. All 4 hydraulic lines need replacing as well. Link to comment Share on other sites More sharing options...
2seater Posted January 1, 2023 Share Posted January 1, 2023 2 hours ago, Alchemy333 said: Feeling kickback at the pedal. I feel mostlikely a wheel speed sensor. I did notice some cracks in one of the lines. All 4 hydraulic lines need replacing as well. Did you read through the help section at the top of the forum? You can get ABS codes through the light flash method from days of old. Also, I found my pedal feel was much firmer after replacing front flexible brake lines, which were in fact cracking. The rears generally are less susceptible since the movement is much less, no rotation to twist them and lower ambient temperature. 1 Link to comment Share on other sites More sharing options...
DAVES89 Posted January 2, 2023 Share Posted January 2, 2023 4 hours ago, Alchemy333 said: Feeling kickback at the pedal. I feel mostlikely a wheel speed sensor. I did notice some cracks in one of the lines. All 4 hydraulic lines need replacing as well. That is due to a bad sensor lead. Most likely a front one. I have an intermittent one myself on the Red. 1 Link to comment Share on other sites More sharing options...
Ronnie Posted January 2, 2023 Share Posted January 2, 2023 On 12/30/2022 at 8:28 PM, Alchemy333 said: Bled the lines... and got brakes. Still feels a bit spongy though... and the ABS light is still on. 4 hours ago, Alchemy333 said: Feeling kickback at the pedal. I feel most likely a wheel speed sensor. I did notice some cracks in one of the lines. All 4 hydraulic lines need replacing as well. If the yellow ABS light is on all the time the Anit-lock system should be disabled. At that point it doesn't seem like the wheels sensors would come into play and cause a kickback in the pedal, but I could be wrong. Dave knows a lot more about the ABS system than I do from experience. So far the ABS on mine has been mostly trouble free and I've not had to do much troubleshooting on it. 1 Link to comment Share on other sites More sharing options...
Padgett Posted January 2, 2023 Share Posted January 2, 2023 If just the ABS light is on there should be a ABS code, see the factory manual section 5E about jumpering the ALDL connector and what the blink codes mean. Pushing back at you is often a stuck main valve. 1 Link to comment Share on other sites More sharing options...
Alchemy333 Posted January 2, 2023 Topic Author Share Posted January 2, 2023 23 hours ago, 2seater said: Did you read through the help section at the top of the forum? You can get ABS codes through the light flash method from days of old. Also, I found my pedal feel was much firmer after replacing front flexible brake lines, which were in fact cracking. The rears generally are less susceptible since the movement is much less, no rotation to twist them and lower ambient temperature. Thanx! Ordered the front replacement lines. Will install and see how it goes. Rears looked ok... for now... still a bit dry though and will replace in the near future. I will look at the post for abs codes. I am familiar with the process for my last project of a 91 Ford explorer. Ill check codes and report back with results. Link to comment Share on other sites More sharing options...
Alchemy333 Posted January 2, 2023 Topic Author Share Posted January 2, 2023 22 hours ago, DAVES89 said: That is due to a bad sensor lead. Most likely a front one. I have an intermittent one myself on the Red. I did notice cracking in the insulation of one of the leads at the hub. Im going to jump the codes to confirm it as only issue. Any info/resources on where I may find proper front replacement leads? Link to comment Share on other sites More sharing options...
DAVES89 Posted January 3, 2023 Share Posted January 3, 2023 On 1/1/2023 at 8:29 PM, Padgett said: If just the ABS light is on there should be a ABS code, see the factory manual section 5E about jumpering the ALDL connector and what the blink codes mean. Pushing back at you is often a stuck main valve. I always thought the push back was due to a bad lead. how does one unstick the valve? 1 Link to comment Share on other sites More sharing options...
Alchemy333 Posted January 14, 2023 Topic Author Share Posted January 14, 2023 Ran the codes finally. 22 (LF Inlet Valve), 32 (RF WSS), 48 (3 Sensors) 76 (RF WSS). All I recognize is the 2 wheel speed sensor codes. On 1/3/2023 at 3:18 AM, DAVES89 said: I always thought the push back was due to a bad lead. how does one unstick the valve? On 1/1/2023 at 6:29 PM, Padgett said: If just the ABS light is on there should be a ABS code, see the factory manual section 5E about jumpering the ALDL connector and what the blink codes mean. Pushing back at you is often a stuck main valve. On 1/1/2023 at 4:53 PM, Ronnie said: If the yellow ABS light is on all the time the Anit-lock system should be disabled. At that point it doesn't seem like the wheels sensors would come into play and cause a kickback in the pedal, but I could be wrong. Dave knows a lot more about the ABS system than I do from experience. So far the ABS on mine has been mostly trouble free and I've not had to do much troubleshooting on it. Link to comment Share on other sites More sharing options...
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