I did an ecu check on my car the other night and discovered that i had code 34. I tested the resistance on the terminals at the det sensor plugs and got: Female plug (to ecu): orange wire to earth = 555k ohms black wire to earth = 00.2 ohm Male plug (to det sensor): orange wire to earth = 566k ohms black wire to earth = no reading (i don't really understand electronics all that much but i assume the black wire on each is just an earth anyway so there shouldn't be any resistance?) I gathered there should be 1000k ohm resistance between the orange wire and earth on the male plug so i decided to plug a 1000k ohm resistor onto the female plug terminals. I proceeded to unplug the battery for 30 mins, checked ecu before starting car to make sure codes were erased and they were (code 55), i drove to work today and checked the ecu once i arrived, still code 55 good. The thing i don't understand is that there didn't appear to be any difference in power between having code 34 and no error. I thought it was meant to be in safety boost while in code 34? Is it possible my car is still in safety boost even though there are no errors?
Maybe your ECU temp sensor is faulty ...>> if your ECU temp sensor is faulty or the connector corroded, then the ECU may think that the engine is cold and run a similar mapping to safety boost.
Re: Thanks Ian. Will check this. Any other suggestions anyone? There is an article here relating to what causes Safety boost. or basically -Engine is cold -Bad Engine Temperature sensor -Car is detonating -Bad detonation sensor The value resistor you used is correct (1Megohm or 1000K Ohm), and it goes to the ECU side of the plug. Sounds like you got that part done OK if your code 34 did not come back. I know that the OEM gauge in the dash is not the best, but I found when in safety boost, the needle would only push about half way to the "7" (equated to about 6.5 PSI for me). When in normal boost, the needle would push about 3/4 the way to the "7" If you are not getting a Code 13, then your sensor is not being detected as faulty by the ECU, but may be reporting that the car is always colder then 60 deg C, and therfore will keep you in safety boost, as mentioned by IB. Best get a boost gauge to determine the exact boost pressure. I don't think the CTS sensor is too expensive either if you need a new one. Good luck
If the ecu no longer controls boost (ie. boost controller/tap) the boost would not be affected either way?? Is that right? I had the same problem with code 34 and fixed it with the resistor and it seemed to make very little difference. I assumed it was because I had a boost controller fitted.
Correct, boost controller normally involves disconnecting the wastegate solenoids which are the ECU's way of reducing boost into safety boost mode for the reasons Pex has listed above. lysergic: I see you've been around here awhile but did you consider : a)the power sensation may be low for another reason (timing, fouled plugs, tired engine etc); b)the difference between safety boost and normal boost is only 2PSI (ish) and unless you are acutely aware of your engine's output at all RPM ranges it is often difficult for a non petrol-head to pick up the difference every time due to road conditions, RPM, spoolup time etc... c) you might also be 'used' to the TT's power and expecting too much for it's current output= time for some mods etc Have you noticed a power DROP from before or just that fixing the code34 doesn't seem to have increased the power ? It is possible of course that the ECU is not sending the earth signal to the wastegates for another reason. Here is a tech article on how to know exactly when you are in saftey boost or not. You can also gain control over the ECU controlled safety boost like this but is not advised until you are CERTAIN that you have eliminated all the usual culprits (detonation, ECU coolant Temp Sensor fault, other engine causes)
I am now getting error 13 so i think i need a new temp sensor because the contacts are clean and still happening
Two things to check with the Coolant Temp Sensor 1: With a multimeter you can check the sensor by measuring the resistance across the terminals which should be around: 2.1-2.9 kOhm at 20C (68F) 0.68-1.0 kOhm at 50C (122F) 0.30-0.33 kOhm at 80C (176F). If in doubt, you can also buy a complete CTSensor from TTZED.com for about $48 etc or if you are a stingy bugger get the best/cleanest looking one for a couple bucks from a wrecker--- dead easy to replace! You'll know it's fixed when your auxilary fan stops running when ignition is on. 2: It might also be the wiring leading to the connectors onthe sensor, they are often bumped and can have a break in the wire inside the sheath. If you are handy with a multimeter, Using this diagram, I would do a continuity check between ECU pin s 28 and 30 and the corresponding pins on the connector plug near the sensor.
zed4life: so if i put the multimeter on the two male contacts at the temp sensor when the engine is at operating temp the resistance should be 300 - 330 ohms? If it isn't should i buy a new sensor?
Correct. Those values are approx unless you have an accurate temp gauge. There could be as much as 5-10% variance even at the exact temps so replace only if it significantly out of scale. A good way to double check is to test when both cold and hot...
