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Mazda Engine General \ F.I. B2200 reving\throttle problemF.I. B2200 reving\throttle problem
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replies 15
following 3
noridetoolow
+1y
Ok...so this started as a "here and there" issue that I THOUGHT was water getting sucked into my intake. But....I have determined this to not be the case. Basically, truck starts and runs fine...but the throttle DROPS out around 2500-3000 rpm. Example....I can put the pedal to the floor with the truck idling in my driveway. It will REV then DROP, REV then DROP, etc..it will keep doing this up and down, up and down. I tried another fuel pump but it didnt help. Another example...I can drive the truck but have to shift out EARLY or the throttle will drop ( by throttle I mean RPMs ). So driving this way I can get the truck to about 55, 60mph but that is it.
I was told maybe an idle sensor, speed sensor...ECU???
Running stock fuel tank and fuel pump ( electronic ). I will note that the tank does at this time have a very small scrape\hole in it. I plan on patching it this weekend. Its not even visible but it maintains a SLOW drip. Not sure if it could effect fuel tank pressure???
91 crate engine, maybe 5000 miles on motor and all hoses, etc...truck was completly rebuilt and motor is new ( 1 year old now?? )
OEM Fuel injection ( conversion from CARB )
Header
Cold Air Intake
Thanks in advance for any help!!
I was told maybe an idle sensor, speed sensor...ECU???
Running stock fuel tank and fuel pump ( electronic ). I will note that the tank does at this time have a very small scrape\hole in it. I plan on patching it this weekend. Its not even visible but it maintains a SLOW drip. Not sure if it could effect fuel tank pressure???
91 crate engine, maybe 5000 miles on motor and all hoses, etc...truck was completly rebuilt and motor is new ( 1 year old now?? )
OEM Fuel injection ( conversion from CARB )
Header
Cold Air Intake
Thanks in advance for any help!!
mazdatweaker
+1y
Could you post some pictures of your underhood area?
How many wires do you have on your O2 sensor.
How many O2 sensors do you have?
What did you do about the wiring harness. . .what did it come out of?
There are tests to isolate problem areas.
Since the engine does the same thing sitting in the driveway, it isn't likely a speed sensor.
Do you know how to use a multimeter?
If you have one, is it digital or analog?
There are low voltage tests and resistance tests that will probably need to be done.
How many wires do you have on your O2 sensor.
How many O2 sensors do you have?
What did you do about the wiring harness. . .what did it come out of?
There are tests to isolate problem areas.
Since the engine does the same thing sitting in the driveway, it isn't likely a speed sensor.
Do you know how to use a multimeter?
If you have one, is it digital or analog?
There are low voltage tests and resistance tests that will probably need to be done.
noridetoolow
+1y
WOW...thanks for the break down....let me get to your questions....
Could you post some pictures of your underhood area? Will do so this afternoon.
How many wires do you have on your O2 sensor. Will take the best pics I can...not sure which sensor is the o2
How many O2 sensors do you have? Dont know
What did you do about the wiring harness. . .what did it come out of? Came from a fuel injected B2200 so its the correct harness
There are tests to isolate problem areas.
Since the engine does the same thing sitting in the driveway, it isn't likely a speed sensor.
Do you know how to use a multimeter? Not 100%...very basics. yes I have a cheap digital Craftsman MM..instruct me and I pay attention well.
If you have one, is it digital or analog?
There are low voltage tests and resistance tests that will probably need to be done.
THANKS!!!! And sorry so long to reply...I have been busy and had to tend to my Integra as well since its my reliable transportation and it gets driven out of town weekly....it decided it wanted new clutch slave and master cylinders, lol
Could you post some pictures of your underhood area? Will do so this afternoon.
How many wires do you have on your O2 sensor. Will take the best pics I can...not sure which sensor is the o2
How many O2 sensors do you have? Dont know
What did you do about the wiring harness. . .what did it come out of? Came from a fuel injected B2200 so its the correct harness
There are tests to isolate problem areas.
Since the engine does the same thing sitting in the driveway, it isn't likely a speed sensor.
Do you know how to use a multimeter? Not 100%...very basics. yes I have a cheap digital Craftsman MM..instruct me and I pay attention well.
If you have one, is it digital or analog?
There are low voltage tests and resistance tests that will probably need to be done.
THANKS!!!! And sorry so long to reply...I have been busy and had to tend to my Integra as well since its my reliable transportation and it gets driven out of town weekly....it decided it wanted new clutch slave and master cylinders, lol
mazdatweaker
+1y
Thank you for posting those pictures. . .
now please go back and do something with them. . .maybe resize them to 1/2 or something.
my computer / internet connection doesn't have a wide enough bandwidth to render them except in "post a reply / edit mode."
Do you have idea how many miles are on the parts you installed?
Have you done anything as far as checking for vacuum leaks?
The O2 sensor is in the exhaust manifold. Take a picture of it.
Take more pictures while you are at it.
Like one facing the front of the engine.
One of the thermostat housing.
One of the fuel injector rail.
One of the airbox.
Is your truck a manual or automatic?
Did the system come out of a manual or an automatic?
Take a picture of your multimeter, too.
Do you know what year the ECU came out of?
And if you could post the numbers off it it might be helpful.
I've worked on fuel injection systems. . .so the principles are all the same. . .but yours is the first FI truck I have come across in Georgia.
now please go back and do something with them. . .maybe resize them to 1/2 or something.
my computer / internet connection doesn't have a wide enough bandwidth to render them except in "post a reply / edit mode."
Do you have idea how many miles are on the parts you installed?
Have you done anything as far as checking for vacuum leaks?
The O2 sensor is in the exhaust manifold. Take a picture of it.
Take more pictures while you are at it.
Like one facing the front of the engine.
One of the thermostat housing.
One of the fuel injector rail.
One of the airbox.
Is your truck a manual or automatic?
Did the system come out of a manual or an automatic?
Take a picture of your multimeter, too.
Do you know what year the ECU came out of?
And if you could post the numbers off it it might be helpful.
I've worked on fuel injection systems. . .so the principles are all the same. . .but yours is the first FI truck I have come across in Georgia.
mazdatweaker
+1y
I found some information that might shortcut a lot of diagnostics.
Since you have a factory wiring harness. . .
According to ALLDATA. . .and with me not knowing anything else about your truck. . .I used a 2wd 2200 MFI selection. . .and found this:
The Test Connector is a green, one pin connector located in the engine compartment. When grounded, the connector activates the self-diagnostic system, causing the dash mounted malfunction indicator lamp (MIL) to flash any codes stored in ECU memory.
Grounding the test connector is also necessary to read malfunction codes with the Mazda Self-Diagnosis Checker or other compatible "Scan" tool.
NOTE: The ECU continuously checks for input device malfunctions, but only checks output devices during the three second period after the ignition is switched "ON" with the test connector grounded. If malfunction codes are present, the lowest numbered code will be displayed first, followed by any others in numerical order.
The connector is located along the passenger fender well, just before the harness enters the firewall.
It seems you can ground the connector with the key off, and then pull the codes from the MIL when you switch the key to the run (not start) position.
If your MIL light is not interfaced with the harness for some reason, I also found this which might be useful:
The Test Connector is a green, one pin connector located in the engine compartment. When grounded, the test connector activates the self-diagnostic system and causes the dash mounted "CHECK" light to flash malfunction codes (California vehicles only).
Test connector signal can be checked at ECU terminal 1E. When ignition is switched "ON," MIL lamp should light for three seconds with terminal voltage reading below 2.5V. After three seconds, the MIL lamp should go out with terminal voltage now reading approximately 12V.
Apparently 1E is an interception point.
If you can pull your codes we can go from there.
Since you have a factory wiring harness. . .
According to ALLDATA. . .and with me not knowing anything else about your truck. . .I used a 2wd 2200 MFI selection. . .and found this:
The Test Connector is a green, one pin connector located in the engine compartment. When grounded, the connector activates the self-diagnostic system, causing the dash mounted malfunction indicator lamp (MIL) to flash any codes stored in ECU memory.
Grounding the test connector is also necessary to read malfunction codes with the Mazda Self-Diagnosis Checker or other compatible "Scan" tool.
NOTE: The ECU continuously checks for input device malfunctions, but only checks output devices during the three second period after the ignition is switched "ON" with the test connector grounded. If malfunction codes are present, the lowest numbered code will be displayed first, followed by any others in numerical order.
The connector is located along the passenger fender well, just before the harness enters the firewall.
It seems you can ground the connector with the key off, and then pull the codes from the MIL when you switch the key to the run (not start) position.
If your MIL light is not interfaced with the harness for some reason, I also found this which might be useful:
The Test Connector is a green, one pin connector located in the engine compartment. When grounded, the test connector activates the self-diagnostic system and causes the dash mounted "CHECK" light to flash malfunction codes (California vehicles only).
Test connector signal can be checked at ECU terminal 1E. When ignition is switched "ON," MIL lamp should light for three seconds with terminal voltage reading below 2.5V. After three seconds, the MIL lamp should go out with terminal voltage now reading approximately 12V.
Apparently 1E is an interception point.
If you can pull your codes we can go from there.
mazdatweaker
+1y
. . .
Tuesday. . .
. . .
kind of wondering why there isn't any information posted by now. . .
???
How hard can it be to jump out a diagnostic port and retrieve codes. . .
???
and post them
???
I may have to start putting deadlines on my response time, as personally, I am discovering that I really don't
like being put on hold as a professional.
Nothing personal.
It's like being caught in a traffic jam / gridlock.
On a Friday.
In 95 degree weather.
In a vehicle with no air conditioning.
Creepy crawly.
Forced to wait for someone else.
Self-induced emergencies, and then making the response team *wait* is not a nice thing. . .
(humming the "jeopardy" tune in my head gets old after awhile)
Tuesday. . .
. . .
kind of wondering why there isn't any information posted by now. . .
???
How hard can it be to jump out a diagnostic port and retrieve codes. . .
???
and post them
???
I may have to start putting deadlines on my response time, as personally, I am discovering that I really don't
like being put on hold as a professional.
Nothing personal.
It's like being caught in a traffic jam / gridlock.
On a Friday.
In 95 degree weather.
In a vehicle with no air conditioning.
Creepy crawly.
Forced to wait for someone else.
Self-induced emergencies, and then making the response team *wait* is not a nice thing. . .
(humming the "jeopardy" tune in my head gets old after awhile)