Explanation of diagnostic data?

justanotherteg

New Member
I have researched on some calculations I found when hooking up my scanner, however some are confusing me and I would like to know if anything stands out as bad to you all? Data was recorded while car was at resting idle and around 700rpm. Thanks for any help. 1998 integra ls stock with intake

Calculated load value-25.1%
Engine coolant temp-374F
Short term fuel trim-35.2%
Long term fuel trim-19.5%
MAP(psi)-0.5psi
Ignition timing advance for #1 cylinder-16
Intake air temp-192F
Absolute trottle position-11%
O2 sensor bank 1 sensor 1 volts-0.035V
o2 sensor bank 1 sensor 2 NOT HOOKED UP
Short term fuel trim bank 1 sensor 1-35.2
 

SeanDA9

New Member
Correct me if im wrong but. Your coolant temp might be faulty as that temp is really really really high unless its actually that hot which is bad. I think your fuel trims are reading rich if that is +35/19 which could mean your car is running lean which would possibly explain your low 02 sensor voltage. Lastly I am not sure how MAP is reading psi? you sure its not a voltage reading or in.hg reading?

edit:is this freeze frame data?
 
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justanotherteg

New Member
Correct me if im wrong but. Your coolant temp might be faulty as that temp is really really really high unless its actually that hot which is bad. I think your fuel trims are reading rich if that is +35/19 which could mean your car is running lean which would possibly explain your low 02 sensor voltage. Lastly I am not sure how MAP is reading psi? you sure its not a voltage reading or in.hg reading?

edit:is this freeze frame data?
I believe that MAP reading is volts. You're exactly right on the lean observations, im throwing a PO171 code and that's why I was hoping some of these readings would help pinpoint something. If I had a vacuum leak I thought my MAP would be off. 0.5V is correct at idle. Which means I shouldn't have a leak correct?
 

db7LS

@Eddie_db7
Im not 100% sure but isnt normal operating water temp 200 +-30~50°F (guess)
In that case a sensor is bad because almost 200° over normal op temp should have blown the cap due to pressure, messed up your head gasket and depending on how your running warping your head and maybe bad piston rings... please tell me im an idiot if im wrong and correct. But i think thats right.

Intake air temp seems high as well unless its a short ram in which case your water temp is high. (Theory works in my head)
 


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justanotherteg

New Member
Yes I have a ram air(warm air intake)! So maybe that's the right intake temp. But the car is not over heating because I think im capable of telling whether my radiator cap is in tack or a blown head gasket. A sensor must be wrong. Im just stumped on these findings and my car running lean
 

Muckman

Not a M0derator
Where does it say your car is running lean?

How can you trust any of this data? Can anyone explain what these values mean? WTF is a calculated load value? Every value has a negative in front of it. Is that a negative value or just a dash between the text description and value? Is MAP in absolute or atmospheric? You have at least 3 sensors throwing strange values - ECT is very high, MAP at near 0psi and TPS at 11% at idle, therefore the rest are suspect as well.

This thread makes my head hurt. Id love to help you but this is junk data without the meaning. /Rant
 

db7LS

@Eddie_db7
Where does it say your car is running lean?

How can you trust any of this data? Can anyone explain what these values mean? WTF is a calculated load value? Every value has a negative in front of it. Is that a negative value or just a dash between the text description and value? Is MAP in absolute or atmospheric? You have at least 3 sensors throwing strange values - ECT is very high, MAP at near 0psi and TPS at 11% at idle, therefore the rest are suspect as well.

This thread makes my head hurt. Id love to help you but this is junk data without the meaning. /Rant
Agreed, pain in the a$$. Retest? Haha
If its running right i say you don't go looking for problems...:???:
 


justanotherteg

New Member
Easy easy fellows I will get more info. Far as the other statements read, I have a PO171 code running to lean so I'd say I have a reason to look why. Those are dash marks not negative, MAP is in absolute. If you don't want to deal with those numbers I will do another test. Work with me guys I have no problem getting you the info how you want it. Thanks
 

Muckman

Not a M0derator
Are you sure that MAP is absolute? With the engine off and ignition on, what is the MAP reading now?
0.035v is very lean, possible bad O2. I would expect engine to misfire and not run right if that were true.
Replace O2 and reset Ecu to clear short term long term trims.
 

justanotherteg

New Member
Are you sure that MAP is absolute? With the engine off and ignition on, what is the MAP reading now?
0.035v is very lean, possible bad O2. I would expect engine to misfire and not run right if that were true.
Replace O2 and reset Ecu to clear short term long term trims.
OK I will let you interpret these numbers(WITH CAR OFF). Hopefully pictures are better so I won't write wrong info.







I also have a pending PO170 code also
 
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Muckman

Not a M0derator
OK you were right about the MAP reading being absolute.
So with a idle reading of 0.5psi that means the intake manifold is nearly at full vac. That's good. I wouldn't say there is a leak there or it would be a much higher pressure (less vac).

And with a positive double digit long term fuel trim like 20% you are running lean and your Ecu is adding 20% fuel overall to try and compensate. Closed loop feedback usually has maximums for fuel trim, probably 20 or 25%. Meaning your'e maxed out on compensation. This is most likely caused by a failing primary oxygen sensor or an exhaust leak upstream of the O2 sensor. Other possible causes would be the fuel system isn't able to the proper amount of fuel, bad/dirty injectors or failing fuel pump or clogged fuel filter.

Here is a website with more information that I found when researching this reply.
http://www.obd-codes.com/faq/fuel-trims.php
 

justanotherteg

New Member
Thanks for the link fuel trims were throwing me off I am more educated on that now. It's a good idea to change my fuel filter so ill do that anyway. I checked injector operation, they all work however they still could be clogged. Also my O2 sensor volts seem way off. I am getting around 1.25 volts on a cold engine reading. Leaning me towards a failing primary O2.
EDIT: o2 is within spec at cold its .175 ill check at idle after I change my fuel filter
 
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justanotherteg

New Member
So one of "Muckman" causes of my lean situation could have been a failing fuel pump. Well yesterday went to start it up and no hum sound from the pump. Checked all fuses. When I checked for power getting to the pump I have approximately 9.5 to 10 volts at the yellow/blue, green, black with silver wires. Also the light green and blue/silver wire underneath have volts. Thick black and thick yellow/green are ground. Here's pics. So if power is here my pump is probably toast???




 

Muckman

Not a M0derator
Cool I actually said something accurate. You should get battery voltage at the pump. Anything less means you have faulty wiring/elec component. That connector looks pretty gnarly. Im not sure which wire is the pump wire but its should be hot with the ignition on.
 
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