New data logger results questions

[thefirstone]

I have just run my first test on my new data logger. I am not sure on some of the results. I have read the various web sites and figure that my O2 sensor is bad since the Air/Fuel results are pegged at the top limit. Can anyone look at this sample and tell me more. Also I am running hot, the fans won't turn on but I get no error code. I replaced the radiator, sensor and everything was fine but a few weeks later the same thing, they won't turn on could it be the relays and if so how do you test for them?.

Thanks

 

[Quasimondo]

How hot is your car running once it warms up? The driver's fan doesn't turn on unless you have the a/c on, the passenger fan doesn't kick in until above 210 (the sensor/switch that controls the radiator fan is at the bottom of the radiator itself and is not seen by the ecu, so you will never get a CEL if that goes).

Your trims are all horribly screwed up and are all maxed out on the rich side. And your oxygen sensory probably is screwed. Try this: Unplug your battery for 30 seconds and then reconnect it. This will clear your ECU and return your trims to 100%. When you're logging, keep an eye on the O2-R value (1G's don't use the O2-F reading so you can just ignore it). When the engine is fully warmed up to around 190*, the O2-R reading should be cycling back and forth between 0 and 1 volt. Take it around the block, if it doesn't cycle at all, then chances are that you have a bad oxygen sensor, which is screwing up your trims because the ecu thinks you're running super lean and is trying to richen up the mixture to compensate.

 

[thefirstone]

Here is a sample of when I am running hot. The fans were working fine then one day just stoped. If I sit in trafic for a while I have to turn on the heater until I get to the freeway.

 

[thefirstone]

Ok, I reset my ECU and ran another test. As you can see I start off at 100% for Fuel trims but after a while they start to creep up. It slowly does this till they reach maximin. Also is my FTO2 suppost to be above 100%. I also noticed my O2-R goes above 1v in certain cases, is that normal.

Tim

 

[Quasimondo]

The FTO2 trim is adjusted based on whatever it reads from the oxygen sensor. It stays in constant motion because the ecu is attempting to keep the air/fuel ratio at the optimum ratio of 14:1. When it's above 100%, the computer is adding more fuel because the oxygen sensor is telling it that it's running too lean. When it's below 100%, it's taking away fuel because the oxygen sensor is saying that it's running too rich.

Based on your oxygen sensor readings (the ones you posted didn't show any readings above 1.00 v) at this point we can assume (for now) that the problem isn't with your oxygen sensor. With your FTO2's constantly above 100%, i think it's time we looked elsewhere for the problem. Post a log of a 3rd gear WOT pull, from 2500 rpm's to redline. I want to see if your car really is running lean by checking if it picks up any knock.

As far as the radiator fan, check all fuses before you start. To test the fan itself, put a 12v source to pins 2 and 4 of the fan connector (pins 2 and 4 are on the right with the tab facing up). If the fan works, then it's either the sensor switch or the relay. To test the sensor, put a ohhmeter to pins 1 and 3 of the connector. With the engine cold (under 160*), it should read open. Once the engine temperature reaches above 185*, it should read closed. If that checks out, then it's the fan motor relay (labeled RAD FAN) in the engine compartment fusebox.

 

[thefirstone]

I don't have a WOT log yet but here is one where the O2 goes over 1v and some 3000 and above RPM data

 

[thefirstone]

Here is a better print out of the 3000 RPM

 

[Quasimondo]

I need a log of a WOT (wide open throttle) run from 3000 rpm's to redline. That way I can see what the ecu is doing when it's in open loop operation and not relying on the O2 readings to provide accurate fuel metering.

 

[thefirstone]

Here is a WOT up to 5800 (ran out of freeway entrance room) and a spot where my O2 sensor whent crazy.

Tim

 

[Quasimondo]

I see the problem with your O2 sensor. It might be an intermittent short in the wiring of the sensor. When you disconnect the sensor, make sure there is no short between pins 2 and 3 on the harness side. Pin 2 sends the O2 signal to the ECU, pin 3 provides the 12v source to the heater element in the sensor. (Pin 4 is ground, pin 1 is not used.)

Another problem I'm noticing is that your TPS may not be properly adjusted. at full throttle, it's only showing 86%, when it should be showing 99 - 100%. It's not a big problem, but it's something that needs to be corrected. It's a lot to explain in this post, so I highly recommend you find either a CD copy of the Field Service Manual, or pick up a Chilton's or Haynes' manual from the parts store (or just do a search for "TPS Adjustment"). They'll explain it better than I can, and they also have illustrations.

 

[thefirstone]

Thanks, do you think the high fuel trim % is from the O2 issue?

 

[thefirstone]

I rewired my O2 sensor an soldered the connection this time. The car runs much better but still some of the fuel trims are not right and now I see some knock issues. What do you think?

Tim

 

[steve]

You don't need to log the flags, EGRT, Battery, Baro, ACLE, or O2-F.

Please note that your running out of injector and actually go static (100% open) past 6k.
The fuel trims indicate that the ECU thinks it running leaner than it should. Either you still have a sensor issue or you might want to replace the fuel filter, rewire the pump, clean the injectors.

Your baseline TPS is a hair high (10.6%) but as Quasimondo points out your WOT TPS is low. That suggests that something is keeping the throttle from opening all the way. Make sure you don't have any carpet piled up and that you don't have excess slack in the throttle cables. (you need to check and adjust the ones in the cruise control pulley as well as the one on the manifold. There should only be a couple mm of slack with the throttle closed at idle and, IIRC, none in the pulley assembly

The coolant temps seem low for a warmed up car.

How old is the knock sensor and have you checked it for leaking goo?

Steve

 

[thefirstone]

I think I have the floor mat issue with the TPS. I have removed my thermostat because of the issue with my fans. I have wired a switch to my air con relay but now the airconditioner turns on when I run the fans (any fix for that?). I am not sure yet if it is the radiator sensor or the relay yet. I have an auto so only 390cc injectors but I bought used 450cc but have not installed yet. I do not know abot how old the knoc sensor is but I will look into it. What field shows me the injector usage?

Tim

 

[steve]

What field shows me the injector usage?

The one right after INJP and before AIRT in your log looks to be IDC (Injector Duty Cycle).
It's a calculated value from Injector Pulse Width and RPM. It's the % of the total time available used to fire the injectors. Once you go over 100% there is no more fuel available even if the ECU wants more. The rule of thumb is not to run more than 85-90% max.

Steve