Alright guys going to give you a quick rundown on what needs to be fixed, what I've replaced, and current issues I'm facing. This is on a 1998 Lexus ES300. No modifications done to it.

Needs to be fixed / Current Issues -
1. Radiator Fans work, but do not power on with AC running or with vehicle at Operating Temperature (according to gauge), the only way they work is by disconnecting the clip connector near the top of radiator on the non AC fan.

2. Car is hesitant when accelerating. Around 20mph it won't upshift until almost 3500RPM. (Rebuilt Engine/Transmission) & I have messed with the throttle cable so maybe that's why, I'm not sure.

3. Cylinders 1, 3 & 5 all keep saying they are misfiring. Now I'm also getting System Too Lean error codes & P0125, P0300, P0301, P0303, P0305 after I took it for a less than 2 mile drive.

4. Smaller-Than-Bagel sized oil leak on ground coming from suspected oil pressure sensor location (have already replaced sensor), so not sure what else to look for.

========================
========================

Things I've replaced to get this car running properly -

1. O2 Sensors (2/3), I have replaced downstream and one of the front O2 sensors, but not the one closest to the firewall near the rear spark plugs.

2. The Coolant Temp SW, located on the left side of engine in-between Cylinder 1 & 2.

3. Cleaned Throttle Body, MAF, & what I could reach on Intake Manifold & installed brand new IAC valve.

4. All new coils, spark plugs & ignition wires. Used all OEM equipment AFAIK.

 

Hello,

A clip near the Top of a radiator? Can you share a picture of the clip in question?

What do you mean by a Rebuilt engine and transmission? Sorry but from your description in this thread and your previous one it doesn't sound like the car was very well taken care of, let alone somebody taking both engine and transmission for a rebuild.

My guess would be that you have a very low transmission fluid level, warm the car up to operating temperature, and while the engine is running, use the dipstick to measure fluid level. Your car should still have Dexron III fluid in it, not the T-IV fluid that came with a later model. Do not use Dexron VI either, while it is marketed as a replacement for all previous Dexron fluids, it has vastly different properties. Amsoil OE ATF is about as good as it gets, though any Dexron III fluid should work.

There is no way of telling anything definitive without a proper scan tool capable of reading Live Data, otherwise it's just pointing at the sky looking for a culprit. I would start by dealing with P0125 code first, as it is likely the reason for the misfire.

A picture of the leak would be quite helpful.

Where did you get replacement sensors?

The one near the firewall is actually responsible for Bank 1, and can very well be the cause of a Lean condition. Check Engine Live Data to see what readings it gives, you should see the value varying from about 0.2V to 0.8V, if the sine wave is higher or lower, like 0.1V to 0.5V or 0.5V to 1V, the sensor is bad. Also floor the car from idle, you should see the sensor go to Rich side immediately and then go back to sine wave.

Check the readouts that both MAF and new Temperature Sensor give out using the scan tool.

New OEM coils are pretty hard to come by for that engine, and wires are even tougher, coils being about $120 each, or about $60 each for good aftermarket. If you paid less for those, or got them from eBay or Amazon, there is a very good chance you got counterfeit junk instead of OEM parts. If you still have original parts and they are in relatively descent shape, I would suggest putting them back in. If you don't have original parts, get low mileage used coils on eBay, they are cheaper than new, and you will have a much greater chance at getting a real thing, as well as Denso or NGK wires from RockAuto, like these ones.

Hope this helps and best of luck!

 

https://www.clublexus.com/forums/es-...ing-rough.html

Same car?

 

Yes, the clip near the radiator in this video - @ the 2:40 second mark.

Rebuilt Transmission I'm not sure of, but as for the engine he claims to have replaced the following -
I just bought a $350 live data scan-tool from Harbor Freight. It's informed me already that O2 Sensor B1S1 is completely dead. When I accelerate the graph stays practically flatline. There is VERY, VERY little activity compared to B1S2 (coming off of engine manifold) & the one fully downstream has 0 activity either but is brand new, I'm not sure if it's supposed to have graph activity due to it not being a AFR sensor, it's only for cat health.

I will try to upload a picture of the leak at some point, right now that's the least of my worries I just check oil and make sure it's in a good spot on the stick.

I got replacement sensors & all parts from Rockauto. The Upstream sensor is a Denso replacement, and I ordered another Denso replacement for the no-activity B1S1 sensor that I pickup tomorrow. The downstream cat health sensor is from some brand from RockAuto, unsure of name at the moment but it's not Denso.

Temp Sensor was reading 180F when I got the needle on gauge to "operating temp" then raised within 5 minutes (all idle by the way) to 208 before I shut it off. Radiator fans never kicked on. MAF sensor while idle was sitting around 0.80LB/min. Highest it got when I accelerated was I believe 7lb/min, no higher than 9lb/min for sure so I think that's a bad reading and the MAF sensor is bad too in addition to the O2 sensor.

Coils were from RA, and the wires are the Duralast from AZ.

EDIT - I should also mention I think it said both of my STFT's were -20%... I don't know if that's good or bad. All of these values were @ idle.

 

Correct, same car. I've posted above with some updated information after going and buying a scan tool that I'll be hopefully returning once this is all done and over with. $350 hit my pockets hard.
The idling/stalling issue is fixed by the way, from that thread. What I did was replace the coolant temperature sensor which for whatever reason made the stalling/hard idle issue go away. Now it's just hesitant on acceleration.

 

Long Term Fuel Trims were at 99% by the way, so there's definitely something going on (I think).
Can anyone tell me what the manufacturer recommended spec %'s should be for all PIDs?

 

That's a temperature Switch on the radiator, it is Normally Closed, hence when you disconnect it, you open the loop, causing all the fans to kick in as a precaution. The fact that this can happen at all indicates that the system is working, and that either the switch is bad (unlikely, they are very durable), or the coolant in the Radiator doesn't reach as high of a temperature as the coolant in the engine.

To check it, measure the continuity of the switch to see if it is open or closed, just to make sure. Then check the temperature of both Radiator hoses, they should be similarly hot. If one of the tubes is completely cold, the thermostat may be jammed closed, preventing the radiator from working. If it is slightly warm, or noticeably cooler than the other, it may indicate either a blockage in the system, like lack of coolant and subsequent air pocket, or a bad water pump.

I may sound a bit pessimistic, but from the pictures you posted in the previous thread, I wouldn't count on any of it being done, and if it was, the quality would leave a Lot to be desired. Not even bothering to clean any of the parts before reassembly is a big red flag.

That is very likely the cause of your Lean Mixture. Disconnect it completely for now, so that the ECU will not be able to reference off of it and see if it will help, the car won't run perfectly, but it should at least get better.

You also mentioned a leak around the radiator, not sure about newer cars, but way back in the day there was a problem with transmission cooler line inside of the radiator getting punctured, allowing the coolant to mix with transmission fluid, which doesn't end well for either. Just make sure to keep an eye on the radiator, as well as coolant and the transmission fluid, if you will see a light film of oil or emulsion in the coolant, check the radiator immediately.

0.8lb/min is about 6g/sec, which is considerably more than it should be, norm at idle being about 3.5 - 4g/sec. Since the engine can't increase its volume, my guess would be that the sensor is going bad and needs a replacement, any junkyard will have one in much better shape.

Was there any particular reason to replace the coils?

Duralast is not one of the brands that I would honestly trust, there were numerous issues with them. If the budget allows, I would get Denso or NGK wires from RockAuto, if not, just keep an eye on your current ones, at least the lifetime warranty on those is right..

Short Term trims are not stored in the system, and will fluctuate all over the place as the engine tries to adjust. What you really need to look at is your Long Term Fuel Trims, or LTFT, they store the running trends from the STFT such that they won't run beyond the limits of adjustment. Here is a very detailed article on this subject, in short, they need to be as close to 0% as possible, anything beyond about 10% is a cause for investigation, with O2 sensor likely causing yours.

Wait what? Never seen that before, I believe the absolute maximum you can get is about 25-30%, though it could come down to a way your scan tool interprets the live data, check it after replacing B1S1 O2 sensor.

I am pretty sure that my barely used $40 Launch tool that I got from Craigslist is about as capable as your new tool, I think I mentioned that option before.. If it's not too late, I would suggest returning your tool as you will likely never need something as pricey for a your troubleshooting. If used is not your option, Amazon has plenty of OBD2 tools in $40-80 range, the tool linked below should be perfectly capable of what you will need, though a used name brand like Launch, Bosch or Innova is preferred.

FOXWELL NT201

FOXWELL NT201

Hope this helps and best of luck!

 

Duralast might have Dorman beat as the worst brand of auto parts.

 

I will be returning the tool, of course. Just wanted something overly capable enough to give me full & clear insight as to what the problem may be. I didn't want to go for just borderline "good enough" when I knew before purchasing I'd be returning it when done anyway.

Replaced coils because they were Toyota OEM according to the stamping on plastic at the head of all 3.
I figured with the engine being 160,000+ miles stock, they should just be replaced if I'm doing Spark Plugs. Why not, they aren't expensive & it'll provide peace of mind and one thing to check off my possible list of causes.

LTFT's were at 99% while idle, not sure what that means. I ordered a new O2 sensor from Denso, which I'll be picking up tomorrow morning and a new refurbished MAF sensor from RA will be delivered by Tuesday. Cost $40 shipped to my door. Considerably cheaper than a junkyard surprisingly. All junkyard prices near me have went up tremedously which is why I've been getting parts from RA as they are good quality and cheaper than anywhere else.

The leak from the radiator seems to only be when the car gets turned off. It's almost like the radiator has too much fluid and it's coming from the resevoir overfilling. I should also mention, before I burped the system today I turned the car off and heard gurgling coming from the coolant resevoir. It wasn't the heater core, haven't heard it sinced I burped it.
Last weekend I took the car driving it for about 3-4 miles to AutoZone, got what I needed and drove back home & when I did I left it on while I installed some seat covers, etc and the Temp got all the way to the H marker and the coolant resevoir started smoking and overfilling, spilling a large amount of coolant onto the ground. I then went and bought 2 gallons of PEAK Asian Vehicle fluid and refilled the coolant. I have also burped the system since then, and keep a eye on it from time to time.

Once I replaced the CTS (Coolant Temp Sens) the leaking seemed to stop along with alot of other issues (hard idle, stalling), only happening again today randomly minus the stalling/rough idle issue.

There's no oil like substance in the coolant fill port, or resevoir tank; only a gold-like flake substance ocassionaly visible in the resevoir which I'm assuming is a coolant seal product the seller added when they sold me this piece of ****. The car has never overheated while driving, only that one time when it was idle and even then I've sat it on idle for 20-30+ mins while Googling DTC's and watching videos with me sitting in the car and it hasn't happened again. Now that I think about it, the gold flakes haven't been visible since the car had a massive coolant leak due to reaching max temperature and overheating. I think they all may have spewn out of the resevoir. I also squeezed the upper hose, and took a shop towel and dipped it in the coolant as I was burping the system to get any gold flakes out of the coolant that rose to the top.

I will replace the O2 sensor once I pick it up tomorrow and post back with results if anything changes. I don't plan on driving the car, it's not my main daily driver until it's fixed so I'm not constantly putting wear on anything. I only drive it after replacing certain parts to get a feel for what's breaking next, or what's been fixed. And even then when I drive it, it's for short periods of time around the block, sometimes getting on a main road to do 45+ (which is where I learned about the hesitant acceleration issue I'm facing now).

As for the engine being rebuilt, when I picked it up it didn't look like how it looks in the photos. That's because I drove it home 2 and a half hours and then it started leaking everything that's leaking. I have photos of him rebuilding the engine, it has been fully rebuilt and I can physically see some of the sealant used in addition to gaskets in more than 1 area. It's orange sealant, also the front drive axles are new too like he stated so I really have no reason to not believe him, but it's always a possibility he's full of ****.

Top and Bottom Radiator hose are the same, hot temperature coming from both of them when the engine reaches OP Temp.

 

NTK coils, the only aftermarket coil I would consider, are about $60 each, almost $200 for something that is not in need of an actual replacement is not something that will pay off. Coils usually don't degrade, they either work, or they fail, so the only time they need a replacement is when they actually fail, especially considering the fact that all 3 of your coils are easily accessible unlike individual coils in a post-facelift. I have a 2000 ES300 with about 230,000 miles, all the coils are still from the factory.

Never thought that rock is shakeable.

One thing that is important to understand is that RockAuto is just a wholesaler, they don't make any parts, and not all the parts they sell are created equal, not all of them are even worth a second look, you are the one responsible for getting a part that fits your needs, and that will last you at least out the door. MAF sensor is a very high precision device, anything other than OEM is likely a big waste of time and money, if it won't fail right away, the readings will be all over the place. If not a local junkyard, places like eBay, or even Craigslist and other marketplaces are still out there, here is a link to a known OEM sensor.

Coolant doesn't expand or contract, doesn't change it's volume, so this issue is likely not caused by an overfill in the system. I wonder if your coolant issues run deeper than just the radiator, it may be that you have a blown head gasket. Below is a video about Test Fluid for Head Gaskets, it will change color if there are exhaust gasses in the coolant, a pretty solid way of determining if there is a problem.


The fact that everything that has a place to leak started leaking right after a rebuild is not all that confidence-inducing, let alone the fact that there shouldn't be any sealant visible after a rebuild. Sorry but to me it seems like that time when it was best to leave it be than to rebuild it.

Hope this helps and best of luck!

 

You're almost always bang on with your posts but this is not accurate. Coolant does expand, around 2% from cold to engine temperature. This might not seem like much but it's enough where the rad cap and overflow are necessary to compensate for change in volume. A working radiator cap is critical to proper operation, as is having no leaks.

On ignition coils, the design of the 3 coil waste spark system means the coils rarely go bad. Don't think I've ever seen a bad one I have replaced wires because of age, although the originals still worked.

 

I can see from the bottom of the coolant resevoir tank, down to the front of the engine bay (headlight area) up near to the radiator along that engine bay frame rail or whatever you'd call it, it's wet. I'm 95% sure that it's overflow from the resevoir that leaks out of the top, flows down the side of the engine bay frame towards the front of the car, and then onto the ground. The leak is always from the passenger side, ends up on the ground in-between the passenger side of radiator, passenger headlight & coolant reseviour tank which is passenger side aswell.

 

Post some pictures of your engine bay.

 

Sure thing, let me go outside quickly and snap some with the flash on and I'll post back here in a few minutes.

 

Here you are. The white dots/splash on everything is the coolant that dried up, or I'm not sure what happened. But it went on everything when the car overheated as mentioned earlier in the thread and the coolant tank started releasing alot of coolant everywhere and smoking.
I also added a video with flash on so you can see the "wetness" I am speaking more about along the engine bay siderail.