I gotta say thanks to all the folks here giving and sharing, its been amazing. When i got my 2010 Pri about 18 months ago, i was mostly hovering around the 42MPG and the car drove great. But about 6 months ago, i got the CEL and P0301 misfire on Cylinder 1, i found myself struggling with 32 MPG consistently. I used the Chevron Progard and it helped for a short while by bumping it to about 35MPG but after a months it went back. Anyways, i read on this forum about cleaning the EGR, checking the PCV and intake manifold cleaning. I did all of that, they helped a bit but after a while my MPG numbers degraded again. Then i read about changing the Spark Plugs, so i changed those as well and nothing improved, this got me disappointed and i still had P0301. Then i read about injector cleaning, so i decided to try that out. When i pulled the injectors, it had so much carbon on it, it was unbelievable. I cleaned them off and used fuel injector cleaner to spray on it. Anyways, afterwards, i got some Michelin Energy Tyres, did some wheel balancing and that was it. Drove the car out and i was amazed that the CEL light cleared by itself, my MPG increased to 56.6 and was still rising. This is absolutely amazing. I think the importance of cleaning or changing the injector nozzles should be better emphasized on PC as a functional solution to remedy degrading MPG situations. My pri has 78k miles it and i got 2 Michelin Saver tyres and changed out the two front Yokohama tyres because they has started showing signs of wear. Attached images are from when i changed the plugs
Good god those are some nasty injectors!! Wow!! Is it advised to dump in a bottle of injector cleaner every now and again?? Thx.
Pretty awesome! Just out of curiosity, how many miles on your Prius? I have a new to me 2010 with about 35K miles and I have noticed that the gas engine seems to start a little rough lately, no codes, just not smooth. Of course this happened after a Toyota Recall so all bets are off. Edited to note that I saw the mileage numbers between the pics. Thanks.
take note, o/p is using nigerian gasoline. most people go hundreds of thousands of miles without cleaning the injectors, and no mpg degradation.
not putting down nigerian gas, i have no idea. there are a few places in the u.s. that seem to get bad gas, not sure why. i've never had trouble on the east coast, but maybe it would take a long time with consistently poor quality.
Well, the point is that this option exists for us amidst all the other options. There are many folks out here that have sub optimal mpg ratings and want an opportunity to increase it. Usually, they'd follow up all the mentioned step but never really think about the injectors. considering how easy it is to change/clean the injectors, I think it should equally be considered.
Good detective work on your part! I am impressed with your "enginuity". Potentially a valid point for non_USA market. I have not personally seen mine so I do not know what I got going on in there. Except I burn all TopTierGas.com (with detergents) and US EPA Reformulated gasoline which is heavily regulated clean gasoline. So I am not expecting much issue. But what fuel options do you have? You may be able to select a brand with better quality or add detergent (eg; Techron). Looks like whatever you are using may have some issues. Can we help you minimize this issue? It could be your gasoline has decent energy content (good MPG) but poops up the system. What I do sometimes (and this is messy and hazardous so you gotta be careful and safe) is I get 1.5-gals of fuel when I fill up in a gaso can. I've checked the gaso pumps accuracy here, and generally accuracy is super duper. So I simply get 1.5-gals in a red gaso can, as measured by the pump, and measure the weight. I normally measure a density of about 0.72 grams/cc whcih is low energy content, but that's what EPA wants for cleaner burning. You can go a step further and mix a small gaso sample with water to get your ethanol content (10% here). The ethanol dissolves in the water, Those are just some simple home tests. In your case, I'd probably go further.
certainly worth a look along with other area's, good point. i'd be curious to hear from people who have had injector problems and at what mileage. i know there are some tecron advocates here, but no proof of value.
Wow! Good thread and good to know about those injectors gets junky as you go along with your mileage. Last year when I reach 15k miles my service man recommended some kind carborator and injector clean up which cost me $125. I don't know how they did it but it didn't help improve my mpg. I guess they just trying to bloat there profit margin. I will check those injectors myself to find out if it was really done or they may have just poured some kind of solution.
Our '99 Montana was notorious for dirty injectors. The dealer replaced 2 injectors under warranty once and I let them clean them twice more before I simply started adding a can of cleaner after every other oil change (much cheaper ). I did this for a couple of years and when the problem didn't recur, I eventually reduced adding cleaner to just twice a year when I filled up for our vacation trips. At some point I had also switched over to primarily using Costco gas and retired so the van got more use. Eventually I quit adding cleaner altogether and had no further problem. The point is dirty injectors are something to consider when mileage drops significantly.
In the USA our gaso quality has probably improved considerably since 1999 and especially since 1990. Sulfur getting down to zero, etc. so there is not much freedom to put lower quality fuels out there and still meet all the specs. But if Nigeria is anything like USA in 1990, there would be more wiggle room in quality. Back in those days sometimes Premium made sense etc. I used to like Amoco Ultimate Clear back then. It was not much more expensive and you could see it was clean.
What the "H" are they putting in Nigerian Gasoline? With fuel injectors that fouled, it's amazing the car was running at all.
I've been looking it up. Apparently mixing petrol with kerosene is rife. That would account for that sort of fouling. Amazing the car ran and I bet it pinked like a good un.
OP : Thanks for pics! IMHO the spark plugs also looked darker than I have seen with post-2000 engines that do not burn noticeable amounts of oil. And the injectors were terrible. OP: Did you check the inside of the combustion chamber for carbon deposits? The reason I mention this is that when I did have spark plugs look like that on motorcycles, I also found carbon in the chamber when I took the heads off, which had to be carefully removed to get compression back to normal and avoid the post-shutdown "dieseling" that sometimes occurred.(Carbureted engines). On a related note: can someone refer me to the correct procedure to do a compression check on a Gen 3 Prius? Clearly my old methods will not work correctly or safely on the ICE of the HSD, and I don't want to do anything that will generate error codes.
i haven't thought before that sod could gather in the fuel injectors beside the egr and manifold. So i did the same and found a big mess of trash so i cleaned it. And i get more liters/100 km than before. Thank you for sharing it Christian
I just did some quick research on Nigerian Oil / gas.. Seems there was or is a major shortage and people can wait in line for days. There are even black market gas stations that sell gas out of bottles and people do the same on the side of the road with a funnel… so if this is true I can easily see how it could get diluted with who knows what or crap could get into the gas along the way.. op pls post up with your experiences on this topic. Thank you.