Dreaded White Smoke

[capnfred]

Ok, well if you have been following my posts regarding my engine and getting it on the step, you know what I have been through, just when everything was going great, no codes, no lites, gas mileage appearing to be good, this afternoon the CEL was back, along with a noticable miss. Drove it home, keeping the idle up, 1500 or so, watching the temp. guage like a hawk..I got home ok, well, I decided to let the engine cool a bit before doing anything else, so I worked on another project for a few hours, I went back to troubleshooting the miss, the only code was 55, knock sensor not working, but I noticed a distinct odor of gasoline, so I looked really hard for any sign of a leak, then I noticed a puddle on the driveway.... hmmmmmmm had my GF run the engine while I looked to see where the gas was coming from, about then I noticed the exhuaust.....white smoke.....sooooooooooo my guess is a blown headgasket worst case, best case is a dead sparkplug..... with fuel injection, the dead cyl. is still getting gas, just not doing anything with it....so the white smoke. Tomorrow is pull the plugs, check the compression and go from there..... the only real puzzle is where is the cas coming from, my supposistion is that the unburned gas is exiting from the blown head gasket.... or ...........only time will tell, or maybe the shadow knows.

any comments or adivice are solicited....

thanks, capn

well, here is the promised update, for some reason the injector for #3 is staying on all the time, thus flooding that cyl. I troubleshot this by first pressureizing the fuel system my jumping FP and B+ in DLC1 and looking for any obvious leaks, none found. Next pulled the spark plugs, found cyl. 3 full of gasoline.....this was because cyl 3 injector was pumping fuel all the time. so now I have to find out why it is on all time (whenever key is on and fuel system is pressureized. Analyzing the ckt. for the injectors, it appears that the ECU fires an individual by putting a ground through the internal transistor. So now I have to find out why I have a ground external of the one in the ECU. Any comments or advice, or am I on my own here?

[blk_on_blk]

Are you sure it's an electrical signal telling the injector to stay open? Could be just an old injector that has stuck open... they all run on a common pressurized fuel rail, so there is always back pressure behind it... if it's old and worn, or stuck open with debris, that could be your issue. You may want to just bite-the-bullet and replace all the injectors... for they are a bit old. I did that in m RX300... $230 for a full set of reconditioned injectors from Motor Man @ http://www.injectors4u.com/ and it runs beautifully now!

[leonmot]

I haven't looked at my engine but it seems that you know a bit about the system. Seems to me the easiest way to check would be to see if you had constant power to the injector. If you do then it would be an electrical problem if not it would be a mechanical problem. Just MHO.

leon

[capnfred]

As for the injector, I was able to ascertain that the problem with the injector was because there was a constant ground from the ECU to the injector. Under normal conditions B+ (12VDC) is applied to all the injectors whenever the key is on. The ECU grounds the other wire, completing the circuit, causing the injector to fire. My problem was that as soon as the key was turned on the injector was open, duping raw gas into the cyl. I got a new ECU, which solved the injector problem. But read on, as it now gets very interesting... While I had the air chamber off to replace the cyl. head cover gasket, I also decided to change the plugs. I was going to use NGK Iridium plugs, but the local Advance Autoparts did not have them in stock, also the Bosch plugs were on sale, so I got 6 Bosch Platinum +2 plugs, I installed them, re-assembled the engine and was rewarded with a smooth Idle, No CEL, and no misfires. All was going well for 1 day, then suddenly with no warning the CEL came on, the engine barely idled, and finally died, I had the car towed to my mechanic, thinking that maybe a wire went bad, (they were just replaced a few days before), he began to trouble shoot the engine. after lots of investigation, measuring the resistance of the wires, checking the spark, and finally measuring the resistance of the individual plugs as a last ditch test. Surprise of surprise, two of the 6 brand new Bosch Platinum +2 were defective, no continuity from the tip to the cap. So we went to Advance to exchange the plugs for two new ones, and being suspicious of the plugs decided to test the new ones before purchase, the store only had 2 left of the Bosch, we checked them both, and they too were open from tip to cap...... so I exchanged the 6 Bosch plugs for NGK iridium plugs....my mechanic explained that had we driven the car for some time we would have loaded the Cat with raw gas, washed the oil from the walls of the effected cyls. and possibly damaged the O2 sensor for the rear bank. I am writing to Bosch to complain, asking for damages, (compensation for towing the car and having to have it repaired). I was wondering if anyone else has had a similar problem with the Bosch Plug. One of the reasons I felt comfortable using Bosch plugs is that they are made in Germany, (which up til now imho = superior quality, and I have have used them for 100's of thousands of miles driving VW Buses.... roughly 700k miles in 4 different VW's. On last cautionary note, because the injector was constantly flooding the cyl. I was dripping gas, I did not want to run the engine with this situation, so to try and find the source of the fuel, I engergized the fuel pump by jumping B+ to FP in DLC1 iaw the FSM. I let the pump run, did not see any leak, so I decided to take a chance and start the engine and try and see where the fuel was coming from. I removed the jumper, and hit the starter, and wow, it just clicked......what had happend was that the faulty ECU filled the cyl. with fuel, causing a hydraulic lock (liquids cannot be compressed). After many expletives, I pulled the plugs one by one, hoping the problem was in the front 3, of course not, it was in the back 3, number 3 to be exact. With the pugs out, I turned on the fuel pump and could hear the gas being sprayed into the cyl. This is when I figured out that the injector was stuck, I unplugged the injector, and it quit, so I then analyzed the problem and learned that the ECU was grounding the injector causing it to stay on. Fortuneately the piston was close to TDC, and I did not damage the engine, I could have bent a rod, or blown the head gasket. Whew! Wonder if anyone has had a similar problem. Oh yeah when I got the engine back to the way the Toyota engineers designed it it ran like a clock, except for billowing white smoke from the exhaust, after a few minutes of running the smoke slowly diminished, and now all is normal... my thought is that the cat/exhaust system was loaded with raw gas, and I had to burn it out.....also before I started the engine I changed the oil as it was contaminated with fuel, and I also poured some oil into the #3 cyl to replace the oil washed from the cyl. walls when the plug was misfiring,,, all in all it was a very educational, frustrating and stressful couple of days.

[SupraMan]

Capnfred, you are waaaaaaay beyond my competence (and patience!) in repair skills. Kudos, I love reading posts like this ... especially with a happy ending. Out of detail interest, how many miles on the beast when this happened?

[capnfred]

the odo reads 180k,

[leonmot]

I would be interested in the reply from Bosch as I too have a high opinion of them. Please let me know.

tx,

leon