Flashing Check Engine And Hesitation... More Complex Then You Think...

[truplaya22688]

Ok, I am going to try and sum it up the best I can, but I can't figure this problem out. 1996 ES300 with 175K now. Car ran perfect until last week. The car ran fine one day and the next day it throws a check engine light and starts hesitating bad, followed by the CEL flashing. The next day I went to Autozone and had them run the code, it turned out to be a cylinder 1 misfire. Based on that I got new spark plugs and wires, along with a fuel system cleaner. Got all that put in and it was still hesitating and throwing the flashing CEL. Then I noticed that my air intake tube was cracked and splitting, so I got that changed, and still the same problem. Next I got 2 out of the 3 coil packs and changed those at $75.00 a piece. Still nothing. I have probably spent around 2-3 hundred with no progress what-so-ever. I will say that the hesitation decreased but its still there. Now people are telling me it could be a vacuum leak or injectors, I really want to figure this out on my own as it doesn't seem like a huge problem but I am not too sure at this point. Any advice would be helpful, I am going to check it out again tomorrow morning but if nothing works I will have to end up taking it to a shop on Monday, I am in college and need a car, but I'm also on a budget which is why I haven't taken it to a shop already. If anyone needs me to clarify something please do not hesitate to ask. Thanks.

[homemechanic]

fuel injectors!

If you have a gauge or some of injector testing device. Great.

If not, try this. Turn the engine on, press a long screw driving against the injector. Listen for the clicking noise by putting your ear next to the screw driver. No clicking noise = problem!

Isolate rather it's the injector wiring or the injector itself. Most of the time, it's the injector that's bad.

[truplaya22688]

fuel injectors!

If you have a gauge or some of injector testing device. Great.

If not, try this. Turn the engine on, press a long screw driving against the injector. Listen for the clicking noise by putting your ear next to the screw driver. No clicking noise = problem!

Isolate rather it's the injector wiring or the injector itself. Most of the time, it's the injector that's bad.

How would I go about changing the injector? I wanted to clean them out at least but I cant seem to get them out, I know that they are located under the Lexus cover right above the first 3 spark plug cylinders and got the wire connector off them but cant get the injector itself out, any advice? Thanks

[homemechanic]

first thing first. did you figure out which injector is bad or dead? cleaning dead injectors is not going to solve your problem.

take the fuel rail off. it's the metal tube attached over the fuel injectors. the rail is typically bolted down by two or three bolts. how do you plan to clean them? if the injector is dead or very clogged up, put in new injectors. typically injectors are cleaned by a high pressure machine running a chemical solution through, not really meant to be cleaned at home. by the time you figured out how to clean them, might as well put in new ones to replace the bad ones. normally not all 4 injectors go out at once. typically one injector go out.

[blk_on_blk]

Your symptoms are classic of a coil pack going bad. Are you sure you changed out the correct one? Changing "2 out of the 3" doesn't mean much if you aren't changing out the correct one (and it means you are changing out good ones if you aren't getting the right one). If it's a cylinder 1 misfire, it's the rear-left coil pack (see diagram). Is that the one you changed?

BTW, here's what it means when your CEL is 'flashing'.

"What does it mean if the (check engine) light is blinking?"

If the light is blinking, a severe engine problem such as a catalyst-damaging misfire is occurring and should be addressed as soon as possible. You can still drive safely, but should minimize your time on the road. Try not to drive the vehicle at high speed or with excess weight (such as towing or carrying heavy equipment).

[truplaya22688]

Your symptoms are classic of a coil pack going bad. Are you sure you changed out the correct one? Changing "2 out of the 3" doesn't mean much if you aren't changing out the correct one (and it means you are changing out good ones if you aren't getting the right one). If it's a cylinder 1 misfire, it's the rear-left coil pack (see diagram). Is that the one you changed?

BTW, here's what it means when your CEL is 'flashing'.

"What does it mean if the (check engine) light is blinking?"

If the light is blinking, a severe engine problem such as a catalyst-damaging misfire is occurring and should be addressed as soon as possible. You can still drive safely, but should minimize your time on the road. Try not to drive the vehicle at high speed or with excess weight (such as towing or carrying heavy equipment).

Well I changed the outer 2, and I tried to swap and switch and know that the middle one is not bad (the old one). If I pull the wire off the pack is still sparking, that means that it should be good right? And there is no rear left coil pack, there is the wire which I did change. I also thought I might have got a bad plug when I bought new ones so I bought one more and put that in and still no luck. Also I heard that its Very rare for all 3 coil packs to go out at the same time. Also as a side note, my firing order is different, when I set it up as the diagram it was barely starting, also I did get my firing order checked out and it is correct, just not like the diagram. Any more advice? Thanks for all those who did help.

[blk_on_blk]

Hmmm... "no rear left coil pack"? ... and your firing order is different? Strange. I'm not sure what to say, for I did some more looking to see if the firing order was different than on our 1995 ES300... it's not. Here's another diagram from another source directly for the 1996 ES300 (unless the Coach edition is more than a trim package). The firing order is 1-2-3-4-5-6. There are six coil packs, and it's a transversely mounted V6, so there should be a rear left coil pack. If the firing order is different, then I don't know what to say, but if the ECU is pinpointing cylinder one, then it probably is cylinder one... where ever that is.

A coil pack can still spark and have it be faulty... the level of spark may not be enough to get full ignition through the spark plug. There could be a problem with the spark plug itself, or a combination.

Yes, coil packs rarely go out in triplicate... not often in pairs, either. It's sporadic when they do go out, too. The best way to know for sure is to have each pack tested for performance.

I still don't know why your firing order would be any different than in the diagram... unless you have some other kind of engine. Several sources say the firing order is the same as presented here.

[George_Jetson]

Hmmm... "no rear left coil pack"? ... and your firing order is different? Strange. I'm not sure what to say, for I did some more looking to see if the firing order was different than on our 1995 ES300... it's not. Here's another diagram from another source directly for the 1996 ES300 (unless the Coach edition is more than a trim package). The firing order is 1-2-3-4-5-6. There are six coil packs, and it's a transversely mounted V6, so there should be a rear left coil pack. If the firing order is different, then I don't know what to say, but if the ECU is pinpointing cylinder one, then it probably is cylinder one... where ever that is.

A coil pack can still spark and have it be faulty... the level of spark may not be enough to get full ignition through the spark plug. There could be a problem with the spark plug itself, or a combination.

Yes, coil packs rarely go out in triplicate... not often in pairs, either. It's sporadic when they do go out, too. The best way to know for sure is to have each pack tested for performance.

I still don't know why your firing order would be any different than in the diagram... unless you have some other kind of engine. Several sources say the firing order is the same as presented here.

It would probably be a good idea to do a compression check, broken valve springs can also cause a missfire

[truplaya22688]

Just got it checked out today by my mechanic, did the compression test and all; said that the M.A.F. sensor has gone bad. What do you guys think? Also he said a new one can run about $400.00

[blk_on_blk]

Could be a symptom of a MAF, for when they go, they can act really weird. Are you getting the same code? CEL still on? I think usually a MAF failure triggers more than one code, but like I said, they can have strange 'partial failures' that give mixed results. I've known people to change out their MAF and have it not be the MAF, but rather something like a crack in the duct work on the air intake.

How did your mechanic diagnose the MAF. Did he specifically test the MAF, which includes a visual, circuit, and component check. He should check the supply voltage, the ground circuit, and the MAF itself, which means connecting a power supply to the correct terminals, connecting a multimeter to the signal terminals, and blowing air through the air sensor.

[camlex]

go to junkyard and it's easy to swap

[homemechanic]

a new MAF runs around $100 @ partsamerica.com.

[blk_on_blk]

One could spend $100/hour for an hour of diagnosing a problematic MAF, or just buy a new one for the $100 and see if that does the trick. I hate to suggest just start replacing parts and see what happens, but with the price for a skilled technician's time, it may be more cost effective.

[truplaya22688]

Ok guys changed the MAF with one from a junk yard, a new was running $225 in Autozone in NY. Still not solving the problem, do you think that I picked up a bad MAF from the junk yard? Car now seems to be a little worse... Anyone???

[blk_on_blk]

I'm tellin' ya, from the symptoms, and from the code you're getting, it's probably a bad coil pack... just sounds like you aren't finding the one that's bad.

[truplaya22688]

I'm tellin' ya, from the symptoms, and from the code you're getting, it's probably a bad coil pack... just sounds like you aren't finding the one that's bad.

But I have a question now, how could it be that I'm not finding the right one because the CEL says Cylinder 1 and thats 1 of the 3 that I changed. The only thing that goes to cylinder 1 is a wire from a coil pack that sits on the 2nd cylinder. I honestly don't know what to do anymore, even the mechanic is unsure, I am going to try another MAF and I'll go ahead and change the last coil pack but I highly doubt that those will fix it. I am beginning to give up on this...

[blk_on_blk]

What's losing me is how you can only have a wire going to cylinder 1... so, are you missing a coil pack? I can't find a picture of the 1MZFE with the coil packs, but here's a BMW engine with the same basic principle... this is a straight six cylinder, but you can see there is a coil pack that sits atop each cylinder... each cylinder has one. The same is true with the ES300 engine... there should be one coil pack per cylinder.... three in the back, three in the front (or three on each side of the engine, since the engine is mounted transversely). You've got to have a coil pack on that number one cylinder.

Is there any way you can take a picture of the engine with the beauty cover removed? That would help clarify things.

[truplaya22688]

What's loosing me is how you can only have a wire going to cylinder 1... so, are you missing a coil pack? I can't find a picture of the 1MZFE with the coil packs, but here's a BMW engine with the same basic principle... this is a straight six cylinder, but you can see there is a coil pack that sits atop each cylinder... each cylinder has one. The same is true with the ES300 engine... there should be one coil pack per cylinder.... three in the back, three in the front (or three on each side of the engine, since the engine is mounted transversely). You've got to have a coil pack on that number one cylinder.

Is there any way you can take a picture of the engine with the beauty cover removed? That would help clarify things.

Not missing, I only have 3 coil packs and from those goes a wire to the back 3 cylinders, here are some pics for reference to what I am talking about. Also if you have a 95 or 96 ES, pop the hood and see for yourself, its hard to explain even with the pictures. And for the life of me I still can't figure out the problem. I am now torn between the fuel injectors or a blown cylinder...

[truplaya22688]

What's loosing me is how you can only have a wire going to cylinder 1... so, are you missing a coil pack? I can't find a picture of the 1MZFE with the coil packs, but here's a BMW engine with the same basic principle... this is a straight six cylinder, but you can see there is a coil pack that sits atop each cylinder... each cylinder has one. The same is true with the ES300 engine... there should be one coil pack per cylinder.... three in the back, three in the front (or three on each side of the engine, since the engine is mounted transversely). You've got to have a coil pack on that number one cylinder.

Is there any way you can take a picture of the engine with the beauty cover removed? That would help clarify things.

Not missing, I only have 3 coil packs and from those goes a wire to the back 3 cylinders, here are some pics for reference to what I am talking about. Also if you have a 95 or 96 ES, pop the hood and see for yourself, its hard to explain even with the pictures. And for the life of me I still can't figure out the problem. I am now torn between the fuel injectors or a blown cylinder...

Ok, so I am more confused then ever, I looked at a repair manual for my car and it also said there are 6 coil packs! I only see 3 in the front the 3 back cylinders only have a wire going to them in my car. Plus my firing order is different from a normal 1MZ-FE. Does anyone have any idea whats going on?

[truplaya22688]

Problem Fixed guys. The wire that comes from the engine and connects to the coil pack was broken apart inside, the connectors weren't making good contact. It kills me that it was something this small and obvious but all in all it was a learning experience. Thanks to all those who gave me insight.

[blk_on_blk]

At least it was something small and inexpensive (unless you dropped a chunk of change on diagnostics with your mechanic... can't believe the mechanic you took it to didn't catch this failure).

Good to hear you found the problem and got it fixed!