BajaRunner

Ok so I got the Actron fuel pressure test kit from AUTOZONE. (Rent). It came with the M8x1.0 banjo bolt to go into the cold start injector!

Well, of course I think the gauge is broken because I am not getting any pressure reading. I tried first with jumping the B+ and Fp terminals. Turned ignition on, heard fuel pump going the entire time, and also heard some sort of leak. Either coming from the injectors or the fuel filter. Never have I smelled fuel though. Just I can "hear" a hissing sound underneath the plenum.*EDIT* This is the fuel return I'd imagine.

Turned over truck, and still no reading on the gauge. Im pissed!

yotafreakshow

there must be a way to bleed off the air in the hose that leads to the gauge while the pump is running? you won't get a reading until liquid is getting to the gauge itself, as fuel pressure might only compress the air in the hose a bit because it has no where to go

BajaRunner

Yeah I just inspected the schrader valve on the end of the gauge and its missing the internal pin. Sweet! Well I'll go back to Autozone and see if they have another one.

So two things I did notice even though I wasn't able to pull the pressure reading.
1) Yesterday after my truck had been sitting a good while, I decided to measure the threads of the banjo bolt at the CSI. I opened it up and there was pretty much no spray or pressure.
2) Today after just getting home and cracking the banjo bolt at the CSI, it sprayed pretty good. I had rag out far enough to see it.

So I feel there might be a loss of pressure over time, and I dont know if thats normal or not.

Are the o-rings on the injectors somewhat visible? If they are, and if I can see them inbetween the injector and the fuel rail on the vehicle, all of them are either melted or non existent.

BajaRunner

Ok, another update. I got a working gauge.

Via FSM:
1) With B+ and Fp jumped, ignition on, engine not running: 45 psi
2) Disconnectd B+ and Fp, started engine, pulled vac hose from FPR: 45 psi
3) Reconnected vac line to FPR: 35 psi

So everything is exactly in spec. If anything the fuel pressure is on the high end with the FPR out of the equation.

Now, my next question is can the fuel pressure still be good even if the flow is restricted in the filter or what?

BajaRunner

Anyways, here is another movie for your viewing pleasure
I know its really hard to hear the miss, but towards the end you can hear it. The video posted above (next to the exhaust) has a better sound of what it sounds like.

Basically the engine starts up and runs really rough until I give it some gas. Then it smooths out a bit. If it idles without any application of the throttle, it will drop idle down to about 600 and stumble, then I hit the gas and it smooths back out. I hope this helps.

BajaRunner

What do you guys think. Should I just go ahead and pull the injectors and send them out? Could this be a probable cause?

BajaRunner

I just went through and tested voltage across the ECU connections, outlined here, (page 21 for 4wd m/t). http://ncttora.com/fsm/1993/engine/27troubles.pdf

Every voltage was dead on in spec. I wrote them all down, but they are all fine looking.

Something tells me its either the injectors, clogged fuel filter or my aftermarket cam (I dont know anything about the cam, the PO just said it was "new" and "oversized").

myyota

I just read your whole thread again and this is the first time that you mention the cam, that is probably the problem right there. It seems when people add cams to these engines that they set them back to stock specs, depending on the cam the stock specs don`t always work the best. What i would recommend is that you try advancing the timing 3-5 degrees and see if that makes a difference, i bet it will.

BajaRunner

Thats funny. Well I have mentioned it in other threads, you were supposed to remember everything I've ever said.

Well I advanced the timing a few degrees to about 8*. The misfire still seems to be there but I haven't driven it yet... I'll report back in a few.

myyota

[QUOTE=BajaRunner;51549193]Thats funny. Well I have mentioned it in other threads, you were supposed to remember everything I've ever said.

Im sorry, ill try and do better next time.

BajaRunner

Well I just drove it around. Same thing!

Really sluggish off the line, sounds choked of fuel or air. Once I get up to 3500 rpm it feels OK. I don't hear or feel a misfire when driving, just an extreme lack of power. It just seems like the engine is starving for something at idle and up to 3000 rpm.


Another thing I've noticed is the engine will start rough. I give it some gas, it smooths out for a while. Keeps idling for about a minute and then will drop down a few RPMS, then pull accelerator and it smooths back out. If this helps anyone?

I'm thinking about testing the TPS for the 5th or 6th time just to make sure Lastly I do appreciate all the support. Its been hard to keep a positive outlook, but at this point all I want to do is get this guy fixed. After driving the other 22re truck this past weekend it makes me remember how fun these are to drive when they are properly tuned. Do you guys think its worth sending the injectors? Looks like I'll have something to drive for the week.

BajaRunner

Any recommendations?! Should I waste my time pulling the injectors or what?

250000_yota

I know it was mentioned up above, but i would check the timing chain timing and valve adjustment. If the chain is a tooth off, ignition timing and injection timing will be off. Just throwin the idea out there...

BajaRunner

Hey thanks man.

Yes I've triple checked it. As long as the cam mark is supposed to be at 12 o'clock then I'm all good. If I tried to move the chain over one tooth, it would probably be more at 11 or 1 o clock.

andykrow

Cam mark at TDC should be just shy of noon (like 11:45 or something )... the tooth just to the right of it should be at 12:00 just about exactly. 4 crawler's timing chain guide has good pictures of it.

http://4crawler.com/4x4/CheapTricks/...ingChain.shtml

BajaRunner

Well here's a picture of the cam gear with #1 at TDC. I think its good.


Speaking of the possibility of my aftermarket cam or valve train causing problems, here are some pictures. The #3 and #4 exhaust rockers look like they are burnt with oil. However the PO said he did the valve work because it was burning oil. I am HOPING that the black burnt oil is from that, and not another, newer issue.

The cam lobe on the #3 exhaust also looks a little suspect. Would that be enough to cause a misfire?

myyota

Its hard to tell from the picture, but that cam lobe doesn`t look right compared to the others.

myyota

When you blocked off the EGR did you notice any difference in power or performance ?.

250000_yota

X2 on the cam lobe. I'd be suspecting the cam judging by the looks of that lobe on #3...

BajaRunner

Yeah I agree its suspect. The wear isn't correct.
However -- Wouldn't the misfire be there ALL the time? I forgot to metion (in this post) that the misfire does go away when the engine is cold start, or in open loop. Or, if the O2 sensor is disconnected. Wouldn't it still misfire if the cam was causing the problems?

And myyota, I had little no no performance gain with the EGR blocked off completely.