billmaness

New to site. Just finished overhaul on 94 22re. I started the engine and set the ignition timing by ear. The engine runs and sounds fine. I have driven it about 15 miles. I decided to borrow a timing light and check the timing. It was set at 37 btdc. When I set it to 12 or 5 it would barely run. The check connector jumper did not have any effect. I pulled the rocker cover to check. The crank is TDC and cam button is up but could be off a tooth? My question is will the engine sound good if the valve timing is off by a tooth? What am I doing wrong?

Matt16

How is your throttle repsonse? I can't answer your question but if it were off by a tooth, I don't think the engine would have much power.

86tuning

check connector jump should put you into base timing if your TPS is working properly.

Check/adjust or replace your TPS as required, then go back to setting timing. Or else set it to 20 deg for now at 900 rpms and then go 'wheeling.

SCYOTA

It will run if you are a tooth off. With the crank at TDC the dowel on the camshaft should be straight up. The mark on the cam sprocket will be at the 11:55-11:58 position. Does your truck idle a little rough and shake some? Usually if your a tooth off the truck will seem fine above idle but vibrate and shake at low rpms.

billmaness

My leg is broke, so I can't drive. (Wearing halo) A friend and I got up to 60 mph and everything seemed fine. good power, etc. I thought everything was great until the timing light showed the notch in the balancer about 1 1/2" off to the left of the scale. The truck did suddenly need idle adj last year. I may have TPS trouble.

Shoua

37? Are you sure? That seems way off. It is possible to have it a tooth (on the cam sprocket) off and still run. If you need to turn the distributor all the way up or down just to have it run, then you are a tooth off. You need to check it out.

billmaness

The adj slot on the dist is about centered with the clamp bolt. there is enough slot left to set the timing to 5, but the engine sputters bad. The chain appears to be installed EXACLTY correct. Dot at 11:58 when on TDC. The removal/insertion of the jumper had no effect on the timing but did flash the check engine light. I did this when holding the timing light.

Flash319

Sounds like you TPS is not adjusted right. You are not getting base timing when you short the terminals. You should hear the engine change when you short. If not your TPS is not right and it will show way advanced all the time. With an ohm meter check the resistance between the bottom 2 terminals on the TPS. When the throttle is sitting closed there should be very low resistance, under 2.5k the manual says. Mine is usually 20 ohms. That terminal is a switch that closes when the truck is at idle. It should then open when you start to open the throttle. If it is not closed you will not get base timing.

thook

You could also set the timing to 12*btdc (without the terminals jumped).....where it would be if you set the timing at 5 when in base mode. In other words, 12 is where it would/should advance to when you pull the jumper after you would set it at 5. That would atleast give you a reference for timing. Setting the TPS and jumping is really the way to do it, though. Making sure it's not gone bad, of course.

Test it thoroughly...
http://www.4crawler.com/4x4/CheapTricks/TPS/index.shtml

Pay attention to this...an excerpt from the above link/page...

"One final test, not listed in the FSM, would be to run the TPS shaft from idle to WOT and watch the VTA-E2 resistance and make sure it increases monotonically, no drop outs or dead spots. If you observe abrupt resistance changes, the TPS could have a burned area on one of the current tracks. See below for a detailed, step-by-step procedure for adjusting the TPS:"

Even if you get it set according to the FSM and ALL reads good and it seems to perform as it should (i.e. your motor goes into base timing) it could still fail this test.....as I've recently learned. I was able to set my TPS and my timing, but I had a hesitation I could not track down and the TPS was the problem according to the VTA-E2 "sweep" test. New one fixed it entirely. Along with my CEL code for the O2 sensor. Not saying yours will be bad or to even suspect it at this point, but it's possible with an old TPS and you'd atleast know that it is indeed good or not. Anyway, I would...it's simple enough.

billmaness

I adjusted the TPS and was able to do base timing. Now, everything is lovely.

NOTE: Chain tracks in the timing cover can be TIG welded and your truck will quit making chocolate milkshakes in the oil pan. It will run cooler too!!!!!!!!

INFINITY

sweet, good job.