rawfeels

I bought a 91 4runner 4x4 3.0L about 2 weeks ago and have been doing maintenance things to it thus far. Mostly because ive been having the usually sputtery, no power under acceleration, hard to start sometimes problems that ive been reading about.

anyway, ive been lurking on this forum since i bought it and have found some useful info. but im a bit stumped right now with my problem.

I have a code 71. So i went to the fsm and just finsihed checking everything out. I had to reroute all the vacuum lines cause the guy had them backwards but other than that, things seem to check out normally.

however, on the last step of the fsm, it says to apply vacuum to the EGR directly and the engine should run bad or stall. well...i clamped the hose on the EGR and nothing happened, i unplugged it and nothing happened. Then i started unplugging all the vacuum hoses from the EGR and the EGR modulator...nothing happened. This thing jsut doesnt stall, in fact, it just stays at the 1.5k idle that it usually has when warming up.

im trying to figure out this code 71 (along with a code 22) but i a bit stumped now.

Anybody have any ideas? Is my EGR setup just completely worthless and needs replacing? Or am I doing something wrong?

thanks

putneysmachine

Just crimping the line or unplugging it will not actuate the EGR. When they say "apply vacuum" they are saying to use a vacuum pump (the small handheld type works perfect).

When you apply vacuum to it, you are opening the valve up (thus causing a vacuum leak by allowing un-metered air into the engine, causing it to run lean). That will tell you if it is mechanically functioning.

You can also find a vacuum line that has vacuum at idle and put that line onto the actual egr and see if it dies or runs rough. Only recommended for testing it, of course.

Terrys87

iTrader: (1)

I am not as familiar with the 3.0, but on the 22re I have always been able to clean the EGR, Modualtor,hoses and connections they go to and get rid of the 71 code and get it running.

If the EGR is similar to the 22re I have listed on my build thread below on where it is at on the first page, how I clean mine and get them working. One day I might have to buy an EGR, but at $150ish, I can get really ambitious.

rawfeels

thanks for the info putney

unfortunately i have a more pressing problem now. the car was getting harder and harder to start until it finally just stopped and died there. it still tried to start and would sputter. then it just stopped altogether.

so i ran the codes again. this time 12 came up (in addition to the 22 and 71). after researching some, i found there wasnt very clear info on it. lots of mixed info about signals from the started to the ecm (which would make sense cause before i changed my battery i was getting a code 43...sta something or other).

anyway long story short, i was tracing wires from the starter. the negative terminal connecting the battery to the starter was all frayed and messed up. So i bought a new one and replaced it. i alsp replaced the belts and changed the antifreeze while i was there.

i went to turn it on again and it went "ca chug" like it was going to try and start....but it just stopped. Now absolutely nothing happens when i put the key in. no beeping sound, no nothing. maybe i blew up a fuse?

MudHippy

You mean by allowing Exhaust Gas to be Recirculated into the engine. The difference not being just semantics. If you were to allow un-metered air at any point past the throttle body, it would actually raise the idle speed(instead of trying to lower it to 0 rpm). This is the principle behind how the idle air by-pass/idle speed adjusting screw on the throttle body works. As well as any other idle up valve(PS, A/C), that redirects filtered air from the air intake to the plenum chamber/intake manifold.

And if you remove any vacuum hose that has vacuum at idle, then you really do have a vacuum leak. I don't recommend doing that personally. Just do as the manual suggests and only remove the one at the top of the EGR valve. When I would test mine, I would just clean the end of the hose off and suck on it like a straw. It doesn't take much effort to open the valve. When it's open you'll know. If it doesn't, then there's a problem.

Wait a second..you did what? You have the starter connected to the negative battery terminal? But you can't do that..can you? And it still wanted to start? Anyhow, positive terminal, not negative.

Yeah, I'd say you probably blew something. A fuse, relay, switch, ECU, I dunno?

Good luck!

rawfeels

i just followed the wire that was already there and replaced it. the positive terminal from the battery went into this harness looking deal with a number of other wires in it. the negative was connected directly to the side of the starter with a 14mm nut. its wasnt connected to the solenoid or anything.

MudHippy

Let me put it this way.

• There should be a short ground cable connected to the body on one end, and the negative battery terminal on the other end. There should also be one end of the engine ground cable connected to the negative battery terminal.
  
• There should be a short piece of what looks like a regular ~10 AWG cable called a Fusible Link, connected to the positive battery terminal on one end, and connected at the other end to a stub of ~6 AWG high strand count cable that is sticking out of the fuse box nearest to the battery. There should also be one end of the starter cable connected to the positve terminal of the battery.
  
• Other than that there should be nothing connected to either terminal, unless you've added something that needs connected directly to the battery for power(ie winch, high-wattage invertor, or for charging like a float/trickle charger, etc.).

+ = Fusible Link(Main) & Starter Cable
- = Body Ground & Engine Ground

So, if you have this cable connected to the negative battery terminal it isn't correctly wired. The starter housing, and everything it's connected to including the engine, serves as the ground conductor for the starter control circuit.

rawfeels

ok i got that all sorted out. turns out i blew up the IGN fuse. I fixed it on saturday. the truck ran on saturday and sunday with the previous symptoms (bad gas mileage, some sputtering/bad acceleration) though the hard to start part seemed to be a non-issue...becuase it started right up.

BUT...this morning i went to the gym. started up the truck and it went fine. get out of the gym and it wont start. it cranks but it wont turn on. i was in a hurry to catch my train so i wasnt paying much attention to it. ill have to check it out this afternoon when i get back home.

i dont get any codes anymore now that i fixed that wire and fuse. previously i had codes 22, 71, 43 and i think a 12 at some point. i believe the EGR and H20 sensor codes were the only ones that were constant. Then they just ALL disappeared for no apparent reason (other than me fixing the fuse and wire). BUT, i did notice an intermittent light since getting it back to running over the weekend. the CEL would come on then go off about 1-2 minutes later. then it may or may not come on again (i only drive maybe 15minutes tops as i dont go anywhere really).

today ill listen and see if the fuel pump is working. And check to see if the rotor on the distributor cap is spinning (crossing my fingers that my timing belt isnt gone). Any ideas?

rawfeels

yesterday the truck wouldnt start. it would try and start it and it would sound as if its going to....but never get around to it. similar to when you pull the cord on a chainsaw and you have to do it 4-5 times becuase your prime button is busted.

anyway, the tow truck came yestrday to take it. and when the guy sits in and tries to hear what im talking about it sputters to life very slowly. "started like its running on fumes" is what he said, and id agree.

the idle went from the normal 1k rpm to above 500 and i drove it to the shop for them to look at it. it drove normally (slow, bad acceleration, a little bit of sputtering at 2.5k-3k rpm but somehow appealing anyway)

i called this morning to ask if theyve found anything out and the guy said that its been starting fine every time and that everything seems fine as far as fuel pressure, air, spark.

no idea what to look for next.

MaK92-4RnR

mines having code 71 now as well, getting the same issues.

markfagus

If you disconnected the battery when you were messing with the starter issue, disconnecting the battery will clear all the CEL codes that are stored in the system.

ToyotaViejo

I wonder if you don't have a few different things going on here.

Your EGR valve and general vacuum system might contribute to your problem, and if the battery lead wire was as bad as you say, I promise that was a problem too.

The way you tested the EGR valve won't tell you anything. You do need a vacuum gun. They're a couple bucks at the parts store. For the amount of vacuum hoses under the hoods of these things, it will come in handy later too.

I can confirm that removing the battery cables will clear the CEL codes. Who knows how old some of the codes in there were?

Now, given the intermittent nature of your problems, I think you have all of the following problems - or should at least look into these areas:

1) Fuel delivery. Start simple. Fuel filter change and a pressure test to make sure the pump is putting out what the injectors need. Be sure to depressurize the fuel system per the manual before opening any part of the system. Fuel can come out fast enough to blind you or break your skin - never mind spraying a highly flammable fluid on everything near it.

2) Sensors. It does sound like something funny is going on with the EGR valve, but you may want to consider an O2 sensor, unless you can test yours reliably. Personally, any time I have a sputtery vehicle with a lack of power and poor gas mileage, I check the vacuum and change the O2 sensor. Sometimes they test as bad only under very specific circumstances.

3) Electrical grounds. You might have a bad ground in your fuel delivery system or in some other engine control circuit. A loose connection at a harness or ground tab will intermittently cause problems as long as it's making some contact most of the time.

Mr.Cheekers

I have been having similar problems, rough idle, no power when I press the gas pedal. I first check my spark plugs to see what they looked like. Number 4 cyl. was white it had a busted injector, went to the junkyard got some new used ones. I changed the typical stuff plugs, wires, cap, rotor, fuel and air filters. The idle got better and the truck wouldn't shutoff, but no power on take off. I found some rusted plugged vacuum lines in route from throttle body to EGR modulator/actuator. The throttle body was also plugged giving no vacuum from ports easy to clean. Air bleed screw Oring was old and hard changed it now the idle is good and takes adjustment. I pulled the exaust and checked the catalytic converter looks great but muffler has a huge hole. Check my plugs after driving awhile and the are white no cocoa brown at all, next checking fuel psi.

Mr.Cheekers

I haven't checked the fuel pressure with my gauge yet. I did remove the fp regulator, I put air through the bottom around 50 psi it went right through with ease. I put vacuum on the FPR air still right through.

Punchy

It will blow right through, The thing is, Is it less then the 50psi amount of air?
What is the head pressure?
the FPR lets an amount through to try and keep a 30-40 psi head pressure.

Mr.Cheekers

Checked the fuel pressure before the rail. Key on position 42psi, engine running 42psi, pinched vacuum to regulator 50 psi. EGR modulator was busted, blowing exhaust pressure into EGR and vacuum lines. I cleared all the steel lines and found the green VSV plugged. I modified a blue VSV (ground off tabs) and connected it. Welded a hole in the muffler. Idles good lacks power wont do a burnout, dammit.

Mr.Cheekers

Other things done, cereal box throttle body gasket. New air filter, greased drive lines. checked gear oils and diffs. New grounds all cleaned and tight. Next gonna check the coolant temp sensor and o2 before cat. (meow)

Mr.Cheekers

Checked the resistance in the coils primary contacts (-+) the resistance was higher than allowed, changed it. I found a new used one in the junk yard, they gave me some cross reference info:

Ignition Coils from these vehicles might work for a Toyota Pickup 6 cylinder (3VZE engine). Info is from junkyard cross reference database.

4 Runner 92 coil; 6cyl (3VZEeng.)
4 Runner 93-95 coil
Camry 94-95 coil; 4cyl (5SFE eng.)
Camry 96 coil; 4 cyl. (5SFE eng.)
T100 93 coil; (6cyl)
T100 94 coil; 6 cyl (3VZE eng.)
MR2 91 coil; w/o turbo (5SFE eng.)
MR2 92 coil; from 2/92 , w/o turbo (3SGTE eng.)
MR2 93-95 coil; w/turbo (3SGTE eng.)
Toyota Pickup 92-93 coil; 6cyl
Toyota Pickup 94-95 coil; (4&6 cyl)

I searched all of these vehicles with no luck. I peeled the sticker off one of the coils common part# was 029700-7051. I found a nice one that checked out to be good in a 1992 Lexus sedan.

Mr.Cheekers

Checked the ECT (engine coolant temp sensor) good per ohm reading at room temp, also boiled water and used thermometer to check ohms as temp increased looked good. I got ahold of the Toyota FSM troubleshooting page, looks like the only things I haven't checked are the IAT( intake air temp sens.) but can't find it and the Heated Oxygen Sensor. I ohmed out the H.O.S. and no good reading and the connecter was green with corrosion. Got some good info @ http://personal.utulsa.edu/~nathan-b...sm/engine.html

Mr.Cheekers

I cleaned the corrosion off the O2 connectors with vinegar and the buisness end with Seafoam and a wire brush. Blew the O2 with compressed air then reinstalled it. This made an extreme difference (WOW) power is back smelled like gas when I first started up. I test drove it up hill had power all the way up. The truck has a little miss now, hopefully with a new O2 it will get better.