Thread closed.
One Missing Precat
1 reading
SRToad4
41 - 60 of 75 Posts
Joined
·
667 Posts
About the missing precat...
About the missing precat. Not everyone knows what a precat is. An owner maybe heard that one could look in the sensor holes and check. Or had a bad sensor and looked in the hole and saw a crack when replacing the sensor. Checking both and one was cracked he maybe just took that one away and left the other intact and remounted the manifold.
Not every MR2 owner is interested in the mechanics of the car but rather just drive it.
About the missing precat. Not everyone knows what a precat is. An owner maybe heard that one could look in the sensor holes and check. Or had a bad sensor and looked in the hole and saw a crack when replacing the sensor. Checking both and one was cracked he maybe just took that one away and left the other intact and remounted the manifold.
Not every MR2 owner is interested in the mechanics of the car but rather just drive it.
Yeah, that's definitely possible as well. Just crazy that the one precat is completely gone, but the car runs/drives absolutely fine. I've read about people first seeing a "loss of power" when the precat fails on them. Would this be felt all around the RPM range? I've never really taken the car over 5k yet, but up to 5k, its plenty fast for what it is.
Joined
·
667 Posts
I don't really know when the VVT-i kicks in and the engine sucks air from the "wrong" way but i think it's when you are cruising at a steady speed regardless of the rev. But i can be wrong...Yeah, that's definitely possible as well. Just crazy that the one precat is completely gone, but the car runs/drives absolutely fine. I've read about people first seeing a "loss of power" when the precat fails on them. Would this be felt all around the RPM range? I've never really taken the car over 5k yet, but up to 5k, its plenty fast for what it is.
Ok, finished up the job today. Flushed out the cat with water, got a little bit of carbon out of it, but other than that no debree/pre-cat material came out. I changed the three amigo studs / nuts, changed all gaskets, and changed oil/filter after bolting everything back together, and so far so good! Car runs great, a little throatier from the other pre-cat being taken out, but that's not a bad thing B)
Joined
·
3,289 Posts
You'll probably find that cylinders 2 and 4 have lower compression than 1 and 3. Time for a new engine. The 1zz had some issues that were resolved in '03, but looks like you didn't dodge the bullet. I want to make it clear that this is an ENGINE problem, not a pre-cat problem. Toyota replaced a bunch of 1zz engine's in the Corolla as well due to the exact same issue. The Corolla does not have cats on the manifold.
Joined
·
3,289 Posts
Reliability issues are why people on here do not recommend rebuilding them. The hatching on these engines is laser etched and it is Toyota's SOP to not hone or rebuild an engine where the hatching or bores are out of spec. So potentially yes you could do a rebuild, but only if everything specs out. a used low mileage 1zz is just a few hundred dollars and will more than likely be more reliable than a rebuild if you get an '03+ engine.
Joined
·
3,289 Posts
If its from a Vibe, Matrix, Corolla (celica?) then you will need to drill an tap the block for the carrier bearing. Not sure if there is anything else that needs to be done.
That is all that I recall needing to be done. Well that and mount it in the rear of the vehicle.
Joined
·
1,444 Posts
First, get rid of the Mobil 1 that's in it. I think the evidence is pretty clear that it's not that great in our Spyders, and this would be especially true in one that's using a lot of oil. Get away from the synthetics for now. Put some 10W-40 dyno or even some 20W-50 dyno or something along that line in it. I would try some of the 10W-40 Castrol first and see if you can slow down the oil consumption. If you're in Arizona the weather there is usually pretty moderate, and a heavier oil should be okay as long as the temperature is above freezing. Keep the revs down on the car, and go looking for a good used engine. At least this way you can still drive the car some if you need to.
I am in the process of swapping in an 07' vibe 1zz, and so far the axle carries holes needing to be drilled are the only difference i've seen. Btw I miss my 05' srt4/orange blast...
Moderate... like when you can't touch certain pieces of your car's interior without being burned when its hot, or moderate like my wife puts on a winter jacket and ear muffs when its 60 degrees in january! :lol:
Joined
·
1,444 Posts
As others have said, yes it's okay to switch. A little thicker oil might help slow down the consumption, and the dyno oil is a lot cheaper if you're going through that much. Any idea what kind of oil was run in the car before you bought it? How many miles does the car have on it? Is the car leaking any oil?
There is really not much basic information about the car in this thread, only that it was missing one of the pre cats.
Also be very careful about checking the oil, this car is different in that respect. The dipstick will lie to you if you let it. Always let the car sit for a few minutes before checking the oil level. slowly spin the dipstick in the tube a couple of times before extracting it to read the level. Pull the dipstick from the car in one fairly quick motion and hold it horizontal to read it. This may sound weird, but it is the only way that I have found that works good. If you do not do this it's hard to get an accurate reading because the oil will not completely coat the end, or run back down the dipstick or some such. I would hate to see you over filling it because of an inaccurate reading.
Your engine is most likely toast, but maybe some of this will help you keep it running long enough to source a replacement.
Good luck.
Joined
·
1,444 Posts
Moderate compared to places like Nome, Alaska......:lol:
41 - 60 of 75 Posts
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
