TX-BLKRUNNER

i'm sorry if this is already said, did not have time to read whole thread, but my efi fuse was out and that caused my truck to turn over but not start, it also would not read on obd2

SpikeStrip

Bet that's it !~

MTL_4runner

Possible, but I thought that shut off the fuel pump?
Definately worth checking though.

AJatx

I took a known working MAF and compared it to my MAF. Pins have identical ohm measurements.

I installed a Optima D34/78 Yellow battery. No change in behavior.

Couple things I noticed.
-Low coolant level. I noticed no coolant came out of the throttle body when I removed it (with supercharger). So, I decided to take a peak at the radiator and I'm really low (2/3 gallon).
-Everytime I crank the engine over, you can smell fuel around the engine bay.
-Sparkplugs are soaked with fuel.
-Compression is about 107psi or so.
-Every fuse relating to fuel and ignition (fuel pump, injection, OBD, STA, EFI) have been checked and triple checked. I even conducted continuity tests on each fuse to make sure. Measured the relays and applied +12V to see if the switch is still good.
I checked the relay in the engine bay and underneath the hood latch.

I'm running out of ideas now.

Should I take it to a dealer or a repair shop? Dealer will have all the right tools and decent knowledge base for each type of Toyota where a shop will probably do what I've already done. Most of my friends' shops are performance related too.

Thanks for all the input! I wish one of the suggestions would've cure the problem.

AJatx

Looks like I need to check ignition again.

I did another spark check with the timing gun and got different results:
-Cylinder#4 didn't get spark (it did before).
-Cylinder#5 has spark
-Cylinder#6 has no spark.
-All fuses and relays check out fine still.

Looks like I need to pull the plugs and check for damage or cracks in the casing.
How often does an igniter go bad? I wouldn't think it would fail often as it's a more reliable ignition mechanism than distributor type of ignition systems.

TX-BLKRUNNER

dude that sucks, i know how it feels, only mine was fixed with a 25 cent fuse. good luck with the problem, toyota techs arent as qualified as you would think, i wasted $600 on labor and a new radiator, and they still did not fix the problem, turned out to be a faulty water pump. go with who you know and wont jip you.

midiwall

Hmmm... Okay, remember that our engines use a "wasted spark" ignition which means that the coil pack actually fires two plugs at once. So, if you're not getting spark on 4 & 6, it also means that you're not getting spark on their kissin' cousin (follow the plug wires to the coil pack, I think it's 1 & 3). Which means... you're only getting spark on 2 of 6 cylinders.

I think you found the core symptom.


Yes, the coil packs can go, but having two go like this would be rare. I'd guess that there's a short (or an open) in the plug wires, or you've got a couple of plugs with cracked housings and they're shorting out to the block.

If you're up for it... Swap the good coil pack with one of the bad ones. If the problem moves with the coil, then I'd say it's the coil. If it stays with the plug position, then it's the plug or the long wire to the driver's side of the block.

AJatx

Thanks for the suggestions. I just came back from Vegas/San Diego.
False alarm on the ignition. For some reason, I thought I would double check the spark by actually pulling each plug out and verifiying by sight instead of timing gun.

I saw blue spark on cylinder #2, 4, and 6.
I noticed that I was too liberal with the anti-seize and cleaned the tips.
Also, I inspected the body for cracks, but all looked fine.
I ohmed out the DIS coils and the secondary impedance is within spec.
However, according to the Haynes manual (96-98 3.4L V6), the primary impedance is outside spec on all 3 DIS coils which I find hard to believe that all failed at the same time. Manual states: "0.67 - 1.05 ohms" and measured on all 3 are 1.5 ohms.

Anyhow, it almost seemed to catch after I pulled spark plugs from #2, 4, and 6 and cleaned them up. I then pulled #1, 3, and 5 and cleaned and inspected those plugs. I also noticed some of the conductor tips (Denso) were loose so I tightened them up.
After installation, the truck still didn't start.

After each attempt, there is a lot of fuel smell eminating from the driver side of the engine bay. The passenger side and exhaust don't have the odor.
I'm pretty sure the fuel lines were attached correctly after fuel pump reinstallation.
It seems that the fuel odor is coming from the big black box on the driver side wheel well (charcoal canister?).

Compression on cylinder #2 is 108psi. I can hear compression on #2, 4, and 6 when I was confirming spark. So, that tells me that I obviously have compression and the timing belt hasn't snapped (I doubted it, but I had to confirm).

Could it be a leaky injector? If that's the case, wouldn't it take more than 1 leaky injector to prevent a cold start? I recall plug in cylinders #3 and 5 having fuel (5 being the worst case). I think plug in cylinder #1 was bone dry.

J

AJatx

I took off the air filter just to see if it was impeding air to the intake.
First start attempt of the day, I heard a "catch" and whoosh of air (as if a hose blow off or compression is made with the plug removed). I couldn't find the source of the noise as it wasn't heard again.

I did see a bit of smoke on the driver side near the bypass area (coupler) of the supercharger (1st gen). The air noise could've come from the coupler.
Definitely smell fuel on the driver side and not the passenger side.

Could the engine be flooded?

MTL_4runner

108 psi is well below the minimum for that engine.
....you might pull the timing cover and verify that the timing belt didn't jump causing the no start.

AJatx

Ok, I re-measured compression on the same cylinder (#2) but this time I made sure the compression gauge hose was on tight and I opened the throttle and gave it at least 8 seconds of turning over.

The gauge read a little over 145psi.

BruceTS

How long have you had the supercharger on your engine?

GSGALLANT

The minimum compression you're looking for is 145psi - in all cylinders. It doesn't give you anything to just check 1 cylinder. Check them all. The maximum difference you should have between two cylinders is about 15psi. If any cylinder compressions are low, pour a little bit of engine oil into the cylinder through the spark plug hole and try the test again. If the pressure goes up, your piston rings or cylinder bore are starting to wear. If the pressure stays low, you may have valve sticking or valve damage or your timing is off.

For your coil packs, borrow another ohm meter and try getting the measurements again to see if you get the same results. All three to have failed at the same time is not very likely.

I notice you didn't install the stock plugs when you replaced them. Any particular reason? I'm assuming you've run these new plugs before successfully since you changed them at 90K and your truck now has 105K, right... so that's not the problem.

I didn't seen any posted results for your fuel pressure. Have you had a change to check that yet? With the truck not running, and the ignition switch to on, you should be getting 38-44psi. Yeah, the test is a bit of a pain to set up and do, but at least then you'll know that your fuel delivery system is OK (at least up to the injectors, anyways). Don't forget to disconnect the battery negative terminal before taking apart any fuel fittings in the engine compartment... better safe than sorry.

Sounds like you have a tricky problem on your hands. Hope you can figure it out.

AJatx

No, I never got the adapter kit to use the fuel pressure gauge.
The pressure could be incorrect even though there is fuel on the plug tips.
I'm going to order the adapter kit so I can get a reading.

I used new plugs, but these plugs are 2 steps colder. You have a point that I'm changing too many things so I'm going to re-install the old plugs.

I read in the manual that 145psi is the low end of compression for this engine. I just didn't have time to take readings from all the cylinders (big storm hit the area).

Supercharger has been on since at least 60k miles (when I purchased it). The previous owner had the kit installed. Due to some noise on the coupler and general sanity, I had Magnuson rebuild the supercharger and I installed it not too long ago.

How does the timing belt "skip" so the timing is off? I just ran out of fuel (even though it could be coincidental).

AJatx

Alright, cylinders #2, 4, and 6 are within 15psi of each other.
Cylinder#2 measured out 155psi this time as I let it crank more (sharp rise and then slowly with smaller increments it reached 155psi). The other cylinders (4 and 6) reached 145psi.

I need to check cylinder #1, 3, and 5 tomorrow.

GSGALLANT

Thanks for the update. Keep us posted. How much is the kit to measure the fuel pressure? You might be able to borrow that from somewhere instead of buying it if it's expensive (Although by looking at it, I guess it's just a guage and hose, a fitting and a longer bolt, so it probably isn't too bad.)
Good luck.

MTL_4runner

The simplest way to see if you have a fuel problem is to remove the intake hose, open the throttle butterfly and spray a fair amount of (sensor safe) carb cleaner into the intake. Then try and start the truck with your foot all the way to the floor and see if it fires at all (it won't fully start but you'll hear it begin to fire up). If not, it is not a fuel issue. If you really want to check fuel pressure, then bring it to a garage and have them do it (a good fuel guage tester setup can be quite expensive). If it does begin to fire, you've found your issue right away.

Those compression numbers still seem very low, but that also may be due to the fact that where you screw the fitting into the head is buried very deep and tough to get very tight so you might be losing some compression because of that. The more critical number would be the difference between cylinders. I would again urge you to check the timing belt marks to make sure they are all lining up properly at TDC.

midiwall

Maybe just a coincidence. But I think worrying about how it could have is less of an issue than trying to figure out why the truck won't start. The list of possible reasons is getting pretty short, and timing is certainly still on there.

MTL_4runner

I've learned that lesson more than once when I worked as a mechanic!!!

AJatx

Starting fluid in the intake did nothing.

I guess it's time to check the timing belt to make sure it didn't slip.
My buddy who works on old cars (60's and 70's) told me to look at the timing belt and to check if the exhaust is somehow clogged.

I re-measured the coils with another Fluke and it was close to original measurements, but a tad bit higher (1.6 ohms for all 3).

Anyhow, time to get to work. You're right, the list is getting shorter. Thanks!