1987 Toyota 4wd manual getting code 6 RPM Signal

[BoostinBen]

So I am about to get my van smogged .. which here in California is a gauntlet of tests designed to try and get cars like this off the road for good in my opinion.. But that being said, i have been able to eek by every time so far .. I usually have a tune up ritual i go through each time I get it done to give her the best of chances ..

This morning, i was just starting that process and decided to run a diagnostic .. and of course .. I am getting code 6 which according to the pdf on here reads RPM signal..

My van seems to run well.. I sometimes have intermittent starting problems with with starter getting signal .. but a few on off cranks and she almost always fires right up.. I feel like it could be a little bit down on power lately .. but that could just be me not driving it as much and my other cars having so much more power.. could be just in my head. It does perhaps seem its running a tad rich if anything.

Any suggestions where i could start ? I was going to check the cap / wires .. plugs before I got into sensors .. but any help is much appreciated.. I will post my progress here as i go in case it can be useful to anyone else here.

cheers!

[Burntboot]

Have you read thru this thread?

How to pass CA smog??? (https://www.toyotavantech.com/forum/showthread.php?1566-How-to-pass-CA-smog)

[BoostinBen]

Yep, Thnx Burn i have gone through that thread. And a lil update here ... I gave the van a basic oil change, cleaned the air filter, and checked the plugs, wires etc.. all looked ok so i decided to roll the dice and keep my appointment I had for this afternoon at the smog station. .. and ... it passed! .. but that being said, I am still quite interested in the RPM signal code i am getting .. so i will still be working through to get to the bottom of it.. per the fsm I should check the fusible link (looked ok visually) not sure if that enough .. then test the distributor, then the wiring between ECU and battery .. then the ignitor.

Not sure if anyone has any experience with this code and can share any insight here as to possible things to check.. otherwise ill just start making my way down that list in the FSM...

Important thing for today is ... it passed! suck it California! ..

[timsrv]

https://www.toyotavantech.com/forum/showthread.php?1722-figuring-out-code

[jannifiddle]

in my experience all that can help, but you can also just find a sketchy smog place in Richmond or east oakland lol.

[BoostinBen]

https://www.toyotavantech.com/forum/showthread.php?1722-figuring-out-code


Thanks Tim, I was looking around for a thread that referenced the code 6 .. Ill clear the codes and check again as a first step..

I am curious though if it is not gone, as the van has always run quite well, could it in fact have a faulty Ignitor or coil or distributor and still run? Like I mentioned before, the only thing I could possibly say is that at highway speeds perhaps its a bit lower on power than I had remembered it to be in the past.. like i have to lay into it a bit more.. in turn perhaps getting lower MPG. ..

Cheers!

[timsrv]

It's not a very common code. I've only seen it on vans that don't run or left over from previous conditions that were resolved. Since our ECU's don't self clear, unless you clear manually, errant codes can be stored for years. When diagnosing issues, it's a good practice to view codes, document, clear, drive, then check again. You should only address the ones that come back, then check again in a week or so to be sure they're gone for good. the van runs, I would disregard code 6 as a fluke. As long as it continues to run, it won't likely come back. If it does, report back and we'll dig deeper. Tim