My 89 22RE automatic 4runner Misses at 90-95km hour occassionally. I installed an aftermarket Tach on the weekend, and it worked fine for the first 2 days. When I drove it yesterday it had no power and missed at any speed. I pulled over and took the Tach wire off the (-) side of the coil, the miss went away. The reason I installled the tach was to see if I had RPM drop when the engine was missing at highway speed. I am thinking the coil may be faulty, or fuel filter. No error codes in the ecm or transmission. From my expirience coils work or they don't work. Could my coil be bad and the tach made it worse? I have tightened all related connections and checked all plug in connectors. The problem seems to be worse when the overdrive is switch off,and the engine is turning a higher RPM. Fuel filter maybe but I seem to have lots of power off the line. I towed my 18' Bayliner last week with my runner and had no problems. I live in B.C. so it is not a flat tow. Any suggestions?

I can't comment on the coil, as I have never had one give me any problems.
One thing I can think of that will cause missing at speed is the EGR valve.

Don't know whether it's your coil or not, but you should be able to test your coil...

I pulled the following from Barney McNamara's archive of Toy mailing lists Toy 4x4 archive, where Jim Brink said the following about testing a coil (Rough Idle thread): </font><blockquote><font size="1" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">quote:</font><hr /><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans"> Check the primary resistance of the coil (+ and -
terminals--should be .05-.07 ohms). Next, check the secondary resistance
(+ terminal to coil wire terminal--should be 11.4-15.6 thousand ohms).
Although not a likley culprit, I would also check the signal generator
(pick-up coil). The spec. for this is 140-180 ohms. </font><hr /></blockquote><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Not sure what year this is for, maybe it will help. The archive is a great resource <img border="0" title="" alt="[Wink]" src="images/icons/wink.gif" /> if you haven't already checked it.... Good luck...

Tom