Power loss/ stumble - Toyota Nation Forum : Toyota Car and Truck Forums

CTG · 07-07-2009, 06:13 PM

Hey guys. So shes yet again giving me grief.
It started as a strange stumble every now and again. Didn't worry a whole lot about it. It progressed to random fits of horrible stumble and no power, shaking badly. Particularly above 3500 RPM. Almost felt like a bad misfire. It would then just go away. Weird... Then it got bad enough it would just croak. Left me stranded twice.

When its happening- Black smoke comes out the pipe. Not blue, its very much a dark grey-black. Off and on you let the clutch out and the revs would remain around 2000-2500 rpm. Stick foot under throttle and pull up and nothing changes. Then it would croak.

I've ohmed out the coil, pickup coil, checked stator air-gap, checked wires, checked plugs, checked compression, checked fuel pressure, check PCV flow, Checked exhaust backpressure, oil level, coolant level, IR-thermometered the water outlet and oil filter....
Everything appears normal.

No signs of oil-fowling on the plugs. In fact, they all 4 look normal. No signs of rich or lean when pulled (I never seem to have my tools when it does happen)

I haven't checked fuel pressure while its happening, pulled spark plugs right after, or such. Just haven't had my tools on me.

I'm going to bring my ignitor into work to run a diagnostic check on it to see if its good.

Beyond that, anyone have any ideas? Its really started to get old...

95 5SFE Sedan 5-speed by the way

Mike Gerber · 07-07-2009, 09:32 PM

It sounds like the car is running very rich when you are having this problem, as indicated by the thick black smoke. Just a hunch here, but check the engine coolant temperature sensor (Toyota calls it an ECT sensor in their manuals) both hot and cold. It may be out of range and causing the overly rich mixture. Have you checked for trouble codes?

Mike

CTG · 07-08-2009, 01:11 AM

My God you're a genius!
I kept pushing back checking them because I've gotten so used to the 2ndary O2 sensor going off from gutting the kitty (despite non-fouler trick) I wouldn't really look.

14 and 22.

14 likely came from unplugging the ignitor.

22- ECT signal out of range.

I'll have to ohm it now.

Its kind of funny- the check engine light actually always went off while it was doing it. I figured it was clearing itself of the 2ndary O2 sensor trip from running richer. (shrug)

Hopefully thats indeed the issue! Why it was intermittent, no idea, but oh well!

BTW, ignitor tested out flawlessly even after 35 cycles.

(mumbling as he steps away from the computer) Genius... I feel stupid now....

Mike Gerber · 07-08-2009, 11:42 AM

"My God you're a genius!"

Not according to my wife!

Mike

Camry LE 94 · 07-08-2009, 02:11 PM

lol CTG cracks me up

CTG · 07-12-2009, 04:23 PM

Lol...

So I replaced the ECT after ohming the old one. Open when above room temp. AWESOME.

I proceeded to flog the crap out of it. Ran better than it has in a long time! Pull home, check for leaks, none. Feeling good, I turn it off and head inside for a snack. I get on the phone with my mentor to let him know its not the hundreds of dollars deal to discover.... Coolant! Everywhere! Like, no joke, its everywhere! On the roof, on the fenders, the hood, the bumper, the ground, my boat... lol. So I look around to find... A 6-inch crack in the top tank of the radiator.

I am now convinced.

My car hates me.

What'd I ever do to it? Maybe it needs some flowers... Or a sledgehammer? lol

CTG · 07-13-2009, 11:34 AM

(insert anger and frustration here)

I am REALLY convinced it hates me now.

I replaced the radiator, purged the air, made sure everything was clean...

And the stumble is back. Its more of a misfire feel now than a general lack of power. It was at night so I couldn't see if it was smoking.

It did feel like a pretty consistent misfire. All 4 spark plug wires are snapped onto the plugs still, no popping or arcing out of the wires onto anything (again, I checked at night and even sprayed some water on the wires)

I have to start my bro-in-laws 93 today so yet again mine gets thrown on the back burner.

Friggin car.

Have to pull the plugs again and run some more checks.

Amusing · 07-23-2009, 02:43 PM

It's time...let's hear from CTG.
What was up?

hoyager · 12-27-2009, 05:35 AM

hi there, i would love to hear what went wrong, your description sounds alot like the grief mine is giving me. 94 5sfe manual.

only happens when its highway hot, and isn't most of the other things to check / replace eg. no egr valve, ect checks fine, new plugs, cap, and rotor, fuel pressure fine, new cambelt / waterpump, 290k, clean TB + IAC, efi relay fine, injectors cleaned, clean air filter..

cheers, andy

***96paseo*** · 12-27-2009, 10:38 AM

Quote:

Originally Posted by hoyager

hi there, i would love to hear what went wrong, your description sounds alot like the grief mine is giving me. 94 5sfe manual.

only happens when its highway hot, and isn't most of the other things to check / replace eg. no egr valve, ect checks fine, new plugs, cap, and rotor, fuel pressure fine, new cambelt / waterpump, 290k, clean TB + IAC, efi relay fine, injectors cleaned, clean air filter..

cheers, andy

Is your ignition timing correct? I've seen teh dizzy loosen up from vibration on a few. Throw a light on it and see if its at 10 degrees BTDC. At that mileage, I'd assume you've replaced your ignition coil?

hoyager · 12-28-2009, 12:00 AM

Quote:

Originally Posted by 96paseo

Is your ignition timing correct? I've seen teh dizzy loosen up from vibration on a few. Throw a light on it and see if its at 10 degrees BTDC. At that mileage, I'd assume you've replaced your ignition coil?

Thanks for your reply, I had not replaced the coil, bought vehicle at 263k k's.
Turns out it is cracked and reading out of range on the resistance (0.9 - 1) for the primary coil, secondary is fine. Its was funny, my dad had suggested coil but I just assumed he was talking about the past...

Cheers