good day , new to the sight .and prius life .i purchased my 2011 last yr. with about 185k. on it . up to 196k now. .loving it so far . but it recently started having a miss on cold start up .not always . and it can last from 1 second to as long as 5 seconds , or so . then it smooths out and runs close to perfect . started the bad behavior on a trip from n. ca. to ok. in early spring . i was driving it pretty hard on the trip. must have averaged 80 mph if not ,i was trying . up to 100 a few times .ran grt. the whole trip , but on cold start up around n.m. in the morning i got the rough start .. cel soon after . has been intermitten since ,with the light going of and on sometimes . it doesnt use a drop of oil ,gets 42 mpg ,and all else seems grt. . i had the ob read and it showed #1 missfire and random missfire . i swapped the plug and coilpack with #3 .and still the same code . the only thing i have noticed is in the morning ,even after a day or more , when i remove the cap on the coolant recovery tank , it still has a small amount of pressure built up . ive topped it off with coolant a few times ,but im not sure it needed it . no sign of overheating .other than that .like i said , motor seems perfect and almost 200k now. otherwise . ive changed the oil in ok before return trip . no usage at all .hard to keep at the legal limit , its so smooth at 80/90 or more! i have no idea what ,if any maintenance was done before my purchase.....any ideas . id hate to let it go if its a maint. thing thnx for read and advice
See EGR and head gasket links in my signature. With your miles, symptoms, and presumably EGR never cleaned, it’s very likely head gasket failure. Leak-down test and boroscope inspection can determine what’s going on. (I’m thinking of making a boiler-plate text of the above.)
is it possible its just the egr ? if its a head gasket it must be leaking very little . more like a seeping head gasket .ive drove it 3000 mi. plus since the first indications and added coolant maybe a pint a couple times . and no over heating or water in the oil ..
I have run a gen3 for 11 years and 265k miles without losing a pint or ever adding coolant. In reality a gen3 head gaskets leak does seep very little at first. Everyone "can't believe" its a head gasket because it runs so good after the initial disturbing cold start rattle. Even most conventional mechanics. I believe the gen3 Prius hgs quickly seal themselves as the engine runs and often do not leak more until the engine completely cools. At least at first. Even then its not every morning, possibly based on the position of the piston and valves. Usually changing spark plugs "fixes" it for a few days. But one day it will get worse and not clear up as fast. It may stumble after waiting at a stop light. At this point, white smoke can be seen at the tailpipe and liquid coolant is often seen in the piston with a borescope. Your chances for a reasonable cost head gasket job go away at this point. A borescope inspection will often detect a cleaner piston early on. See "The Car Care Nut" video on head gasket diagnosis with a borescope. It does require a good scope, not one of the $20 specials. Sealer sometimes works for a few weeks to months. In a way it is diagnostic since the problem goes away, effectively proving a hg leak exists. You risk the radiator, heater core, blockages and more with a sealer. Often the engine needs replacement later on and the heater core or radiator is also a problem.
Eric O from South Main Auto in northern NY state tonight discussing testing for hg leaks. This one was advanced from the sounds of it.
The EGR is the cause of the leaking head gasket. The leaking head gasket will be the cause of the OTHER CEL (change engine light.) Stop Drop Roll STOP driving the car. DROP your oil to see how ‘milkshakey’ it is. Switch to 5000 mile Oil Change Intervals. ROLL your car into the garage (or A garage) to immediately clean the EGR. Then assess the damage. A leaking head gasket is like a heart attack. There ARE no ‘very little’ ones. The best you can hope for is a non fatal, expensive, life-changing event. Good Luck.
well ,dont ask the question unless your ready for the answer ! .... so the next question is , is a 10 yr old 200k car worth the time , effort and expense of putting a head gasket on .?and what are the expectations if i do ? i just watched a utube on the replacement and it looks to be easy for the people that do it regularly .first timer im not so sure . what would be the shop time/price be and should i expect it to be a success . might be time to trade up . i assume my high speed trip to ok might have been a bad decision hindsite really sucks , dont it !
I would call Gasketmasters in the Bay Area and ask them about options. Many think getting another 50k-100k on a 200,000 mile car is worth the money. A lot depends on your financial situation and reliability needs. If the car was bought for a reasonable amount without payments it may make it easier to spend a few thousand on the engine. Some can only consider repairs. Some need high reliability. Some can afford a newer car even in this inflated car market. Some can't. Reliability is not just a function of a head gasket with this generation. If someone has already changed the brake booster and hybrid battery the car is a better candidate for engine work. Any engine work, regardless if its a $1500 head gasket or $5000 rebuild, needs to properly clean the intake, throttle body, egr components and pcv system. Often the head needs to be machined even on a simple head gasket job.
im sure on the fence at this point . the bay area is 300mi south of me , so not really a option . my nearest large city is medford or. ,if you can call it big . way bigger than yreka ca . if i were certain i had a chance at 50k plus i would almost certainly attempt repair . but , the other issues that you mention are a big question . i dont believe any of them have been delt with . the car does ,even now drive grt. and im a ptius fan now either way . i would sure like to find a low mi. prius , but the prices that people are asking in this area is completely insane . i might attempt the repair myself . seems a bit more complex than a sbc head gasket . but with a step by step u tube it is possible . just might take a full day . its the first step thats the hardest . i hope ! for now im im hoping to find someone local with real experience .i guess toyota dealer would be cost prohibitive ?
I think a diy head gasket job is a week long effort for a first time diy'er. With more chance of problems especially with the timing and wiring. You may need to have the head machined. Call Gasketmasters and talk. They have mobile service the last I heard. Maybe they would meet half way. Obviously talk to the dealer and any shops around you someone recommends. Go to the local shops, don't expect good info on the phone. The dealer may want a diagnostic fee. Some shops will not recognize a Prius head gasket symptom and may not have a borescope. Any engine service could esculate after a teardown if other components are bad. Otherwise, small does not mean bad. Sometimes a small shop is run by the better mechanic. Clean, organized, experienced with references is the key. Finally the dealer may be able to look up your vin and determine if Toyota repaired the brake booster, hybrid battery or inverter in the past. Knowing these things is good but not essential.
The car is doesn't use the EGR system at idle, and not during cold run operation. EGR clogging often results in misfire during part throttle accel on a warm engine. Misfire during cold start is a strong indicator of the initial stages of head gasket failure. A small amount of coolant gets into the cylinder while the engine sits. Just enough that it fouls the spark plug for a few seconds until moving gases "blow dry" the plug and it can spark the combustion process again. Testing would be to use a special pump to apply pressure to the cooling system overnight. Then pull the plugs and inspect the cylinders for coolant with a videoscope the next day. Or set #1 cylinder to top dead center (on compression stroke - all valves closed)- then use a leakdown tester to pressurize the cylinder with 100-150psi compressed air and see if pressure builds in the cooling system. Posted via the PriusChat mobile app.
If you're considering head gasket repair, also consider Luscious Garage. I would be wary of Gasket Masters.
Could just be, given the right temps and humidity, condensation in the air intake, which can cause very rough start. It is a known problem with the 2010s and the air intake was later modified to reduce this problem. SM-G960U ?
if the pressure in the coolant recovery tank after setting overnight is not normal, then i have to think its pretty certain that the hg is leaking . i just need to put on my big boy pants and tear it down . leek is at best a seep at this point so the sooner i repair it , the more chance it will be successful. possibly !
well i just spoke with a guy semi local that says he does hg for $1000.oo parts and labor . and , 24 hr turn around sounds like a hella good deal to me he said if the rod is bent another couple hundred more . anyone think this is too good to be true ?
