I have been on this forum many times and have almost always found answers such that I never actually posted anything. I am hoping someone else has run into the problem and can point me in the right direction as I am completely stumped
My 1999 100 series with 276K miles (original owner) started stalling last week when slowing down or at low idle. After some digging, it seems that once the engine gets warm and the ABS pump turns on, it seems to kill the engine. You can see the RPM’s drop to almost zero and sometimes it tries and succeeds in revving back up, others it stalls. It starts right back up, but this is obviously a big problem.
When this issue started a week ago, I decided to pull the IAC motor and clean the throttle body. After checking the IAC with an Ohm meter, I wound up replacing it with a new one. I also replaced a couple of the vacuum hoses that were a little suspect and the PCV valve. It seemed to run great for a couple of days, but I didn’t really drive it very much so I suspect I never got it warm enough.
Then while driving about 7 -8 miles from home, it started stalling again. Then the ABS lights and warning sound came on.
I limped it home and started trouble shooting.
A little background and context. Last year the ABS lights came on with no brakes etc.… I wound up replacing the ABS pump only with a new one. Everything worked great and no issues with the brakes since then.
Following is what I am seeing:
When the vehicle is cold, it starts just fine, idles at around 1K RPM’s, the brake booster runs fine and no issues.
It seems like once the engine gets warm, it starts stalling even when idling in the driveway. I have been able to determine it stalls every time the Brake booster pump starts. I can sit in the car, pump the brakes and it will stall. I pull all the ABS relays and it never stalls. (Obviously this is not a solution since I no longer have brakes)
I am trying to not just start replacing a bunch of things until I have a little better idea of the direction. It seems to me that this could either be an electrical issue where the booster pump is dropping the voltage enough to cause the vehicle to stall? I hooked up my OBDII wireless (I use iCarDoc) and it’s not throwing and DTC’s. I can see that the ECU voltage is right at 13.5 to 13.8 Volts while its running. I do see a drop when it stalls, but I am not if that is cause or effect?
With 276K miles, I went ahead and ordered new Denso fuel pump and plan on replacing it later this week.
So here is my question, how could the ABS be causing these stalling problems?
Is it electrical? Is it some kind of short or ground problem that is dropping the voltage?
Is it potentially the fuel pump going bad and it’s just coincidence that when the ABS pump comes on it just enough to push it over the edge?
I have looked for vacuum leaks, and don’t seem to find any?
I am stumped on which direction I should go and am hoping someone else may have some experience or advice to point me in the right direction.
Thanks in advance for the help
My 1999 100 series with 276K miles (original owner) started stalling last week when slowing down or at low idle. After some digging, it seems that once the engine gets warm and the ABS pump turns on, it seems to kill the engine. You can see the RPM’s drop to almost zero and sometimes it tries and succeeds in revving back up, others it stalls. It starts right back up, but this is obviously a big problem.
When this issue started a week ago, I decided to pull the IAC motor and clean the throttle body. After checking the IAC with an Ohm meter, I wound up replacing it with a new one. I also replaced a couple of the vacuum hoses that were a little suspect and the PCV valve. It seemed to run great for a couple of days, but I didn’t really drive it very much so I suspect I never got it warm enough.
Then while driving about 7 -8 miles from home, it started stalling again. Then the ABS lights and warning sound came on.
I limped it home and started trouble shooting.
A little background and context. Last year the ABS lights came on with no brakes etc.… I wound up replacing the ABS pump only with a new one. Everything worked great and no issues with the brakes since then.
Following is what I am seeing:
When the vehicle is cold, it starts just fine, idles at around 1K RPM’s, the brake booster runs fine and no issues.
It seems like once the engine gets warm, it starts stalling even when idling in the driveway. I have been able to determine it stalls every time the Brake booster pump starts. I can sit in the car, pump the brakes and it will stall. I pull all the ABS relays and it never stalls. (Obviously this is not a solution since I no longer have brakes)
I am trying to not just start replacing a bunch of things until I have a little better idea of the direction. It seems to me that this could either be an electrical issue where the booster pump is dropping the voltage enough to cause the vehicle to stall? I hooked up my OBDII wireless (I use iCarDoc) and it’s not throwing and DTC’s. I can see that the ECU voltage is right at 13.5 to 13.8 Volts while its running. I do see a drop when it stalls, but I am not if that is cause or effect?
With 276K miles, I went ahead and ordered new Denso fuel pump and plan on replacing it later this week.
So here is my question, how could the ABS be causing these stalling problems?
Is it electrical? Is it some kind of short or ground problem that is dropping the voltage?
Is it potentially the fuel pump going bad and it’s just coincidence that when the ABS pump comes on it just enough to push it over the edge?
I have looked for vacuum leaks, and don’t seem to find any?
I am stumped on which direction I should go and am hoping someone else may have some experience or advice to point me in the right direction.
Thanks in advance for the help
