| Author |
Message |
Steve Magnusson (91tr)
| | Posted on Saturday, February 24, 2001 - 11:56 am: | |
James -- unfortunately, from a recent experience, I can tell you that you can still have a bank-related fuel delivery problem downstream from the pumps/filters (1. many small "passageways" in the metering heads and the injectors themselves for that matter, and 2. there are separate fuel pressure regulators mounted up by the metering heads). David's advice is spot-on that poking around with a timing light can reveal a lot about the health of the ignition side of things. If that seems OK, then I'd suggest that you measure the O2 sensor voltage outputs at about 2000 RPM when the problem occurs (after warm-up so the air injection system is "off") -- a low reading less than +0.2 VDC would indicate a lean condition (fuel delivery problem) while anything greater than about +0.9 VDC would indicate over-richness. The O2 sensor outputs are the single-wire connector coming from each O2 sensor (the two-wire connector is +12V power and ground for the built-in O2 sensor heaters). |
James Pai (Jaymus)
| | Posted on Saturday, February 24, 2001 - 6:21 am: | |
Thanks for the information. The dealership told me it was my right banks, they changed both fuel pumps, so fuel delivery systems should be functional. Thanks for all the help.
I'll take it into another shop soon, I am not satisfied with my current repairs at the dealership.
If anyone has anymore suggestions, please post them.
James |
David Prall (Davidpra)
| | Posted on Friday, February 23, 2001 - 5:13 pm: | |
In fact it is quite easy to diagnose and isolate an ignition miss. Using an inductive pick-up timing light, survey all (12) plug leads and observe the cadence of the strobe patterns -- most misses can be detected visually by noting anomalies in the pattern(s). If all the errors are in one bank only, move to the (2) HT leads supplying each bank to resolve whether the problem is in the "bank" supply or in the individual cylinders.
If no ignition faults are detected, start looking at the fuel injection system. |
Steve Magnusson (91tr)
| | Posted on Friday, February 23, 2001 - 9:05 am: | |
James -- how do you know that the "misfire" is only in the right bank? Unfortunately, these are complex systems so without some diagnostic measurements I don't think you'll get beyond the rather unhelpful statement: "something's wacky in the ignition or injection systems". That would be the first step -- to determine if it's a spark or fuel delivery problem. |
James Pai (Jaymus)
| | Posted on Friday, February 23, 2001 - 5:31 am: | |
I need some help to figure out what can be causing this. I don't work on my own TR, but I Would like to know what can be causing this. I know my alternator has to be rebuilt also, it's making loud noises. (The dealership informed me of that).
The car idles and misfires intermittently, and almost stalls, but after it warms up a while, it seems ok. However, while driving it misfires and lags due the right banks misfiring!!
I noticed the car has been rough at idle prior to the misfiring problem, the lag/misfire on right bank only started recently!
Help!!!! |
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