ToyYoda

I jumped the connector for timing according to the chart under the hood, it didn't change anything but the check engine light started blinking. I have set the timing to 5° BTDC like it said but at that point, the engine was so far retarded, it was terribly slow and unresponsive. I have it, according to my timing light, way far advanced but it runs much much better when I just tune it by giving it gas to hear the throttle response. Did my timing chain jump? What could be the problem? Maybe someone installed a new chain and was off a tooth? I also hear knocking when it's being started but only for a second, is that normal?

Saint_Berzerker

So, if I hear you right, you jump the connector and if you adjust the timing notch to 5 degrees it almost dies out because it's too slow?

Try getting it as close as you can, and then turn up the idle speed screw to bring the engine speed up. That way, it won't die on you...then turn the distrib down, then idle...etc, etc...just keep messing with the idle screw then distributor until you get it close.

Did you have any work done on it recently or did it just start acting funky? It's not going to run right or give you good power just advancing it like crazy so it runs.

A while back I messed with mine forever and finally got it right.

Did you make sure that your idle speed was set right before you jumped the connector? And that the engine temp was in the middle before messing with it? It has to warm up first.

ToyYoda

I always let it warm up before changing anything related to timing or idle. When I set the timing to 5 degrees, it will stay running but like I said before, it just doesn't go anywhere. It bogs and has no top end. Right now where I have it, I get excellent acceleration through the RPM range and no detonation. It runs very well but according to the timing light and distributor, it's advanced way past the mark on the crankshaft pulley and timing marks on the block. My idle speed was one mark below 1k RPM while timing.

tomasp

Adjust your TPS, man

toyaholic

yeah, tps, if the idle does not change when you jump the connectors, itneeds adjustment. after you get that dialed in and get the timing set , if you still have the sluggishness then i would say that you are a tooth off on the crank to cam.

Flash319

Do a search.........................TPS

Saint_Berzerker

Yeah, if your idle doesn't change it's your TPS. Your idle should drop down a few ticks when you jump the diag port.

ToyYoda

So is the TPS bad or just needs adjustment? It's never been touched so I'll start messing with that and getting it dialed in. Would that also be what is causing the truck to take a few cranks and me playing with the gas to get it started when the engine is cold?

ToyYoda

IDL and E2 show infinite resistance at all throttle openings, all other tests checked out. I guess I've got a bad TPS?

Flash319

You should be able to adjust that so that it shows a closed switch condition. Usually less then 30ohms.

ToyYoda

I just replaced the TPS and was able to tune it properly and got my timing perfect now. The old TPS spring was worn out and wasn't springing back like it should. My throttle response it much better too. Thanks for the help!

highway74

OEM Toyota TPS? What did it cost you? I had a similar problem the other day.

ToyYoda

I payed $92 after tax for a Borg Warner TPS which is way too much and you can find a better deal but I didn't want to wait.

webstar-design

Just got this 4X4 4runner real clean. On the way home it didnt have much power going up hills. The first thing I was going to do was check the timing. When I jumped the connectors the idle did not change. Humm whats up with that?, found this site and found the old TPS problem. adjusted the tps and reset the timming, runs hella better.. but the idle still didnt change when jumping the connectors to get true timming setting. I got a new TPS I hope this works. Thanks for the info

bodo

Just a little info for you guys that are running 89's. Toyota changed the TPS in 02-89 so look at your decal on your door to see what you need or call toyota and give them your VIN#. Half of the parts houses didn't know this and would have given me the wrong one which will drive you crazy trying to adjust, believe me I know.

webstar-design

Sep.29 I put a new tps on and today Oct.11 i got a check engine light for about 5 seconds with error code 41. Do you think its out of adjustment?

bodo

Pull your negative battery cable for about 20 min then drive around for a few miles. Put your jumper in and if you still have the code then it's still off or if you bought it from NAPA you've probably got the wrong one. Call Toyota with your VIN# and then cross that part# with the parts house#. Oh yeah reset your radio presets.

tomasp

You HAVE to adjust TPS if you take it out / put it in. Once you do that at least once you will know how easy it is to get it wrong.
Take your throttle body out, get some feeler gauges, set everything as per FSM/websites (you will find links in Yotatech), put it back on TB and on the engine.
Then pull the EFI fuse out for a few minutes and back in. Done. No need to disconnect the battery at all.