shaking engine and check engine light
- Thread starter madsmartguy
- Start date
Bad O2 sesnors cause a rich condition not lean.
MazdaSpeeder
Member
- :
- Protege5 (5-spd)
Anyone else realize this thread is a year old...I'm guessing he got it fixed by now...
Yes, it has been resurrected from the dead. Bwahahaha!
BlueMazda3s
Member
Sounds like the EVAP Solenoid is stuck open.
I had this same problem with my 3. I had read that the EVAP problem is very common on these mazda's, so instead of going through the multiple visits to the dealer i figured it could be fixed. If you take off the evap solenoid and look down in it, you will see a little screw slot. I screwed this out as far as it would go and put some penetrating oil into it and blew it out with an air hose. Then I tightened back up pretty tight. Reset my Engine light by disconnecting the battery. No check engine light now. Also my car was missing when at an idle caused by the evap solenoid being stuck open. This fixed my check engine light and the miss.
Hope this helps!!!!
I had this same problem with my 3. I had read that the EVAP problem is very common on these mazda's, so instead of going through the multiple visits to the dealer i figured it could be fixed. If you take off the evap solenoid and look down in it, you will see a little screw slot. I screwed this out as far as it would go and put some penetrating oil into it and blew it out with an air hose. Then I tightened back up pretty tight. Reset my Engine light by disconnecting the battery. No check engine light now. Also my car was missing when at an idle caused by the evap solenoid being stuck open. This fixed my check engine light and the miss.
Hope this helps!!!!
where's the evap solenoid??
my car is basically doing the same thing.
initially my car had a huge hesitation problem, between 2-3krpm. i brought it into the shop and they found out my tensioner spring on the timing belt was busted. caused the belt to slip 2 teeth and all kinds of rough engine business. funny thing though...idle was still okay. no engine shaking. it had 2 or 3 idle deaths at a stop, but otherwise held idle fine.
i get the car back from the shop...the loud engine noise caused by the bad tensioner spring is gone, but now i have this rough idle. the engine is shaking like crazy and the car sounds like it's going putt putt putt putt. once i get the rpms up a little bit, even just a couple hundred, the car runs just fine.
it threw a CEL as i was driving away from the shop and so went back. it was a p0300 code. he said he inspected all the valves and such when they put the timing belt back, to make sure there wasn't damage due to the timing belt slipping, and there was no valve damage (thankfully).
so what gives?! something happened between them fixing it and me getting the car back. no more crazy engine noise and hesitations from tensioner, but now i have a really really bad idle!
initially my car had a huge hesitation problem, between 2-3krpm. i brought it into the shop and they found out my tensioner spring on the timing belt was busted. caused the belt to slip 2 teeth and all kinds of rough engine business. funny thing though...idle was still okay. no engine shaking. it had 2 or 3 idle deaths at a stop, but otherwise held idle fine.
i get the car back from the shop...the loud engine noise caused by the bad tensioner spring is gone, but now i have this rough idle. the engine is shaking like crazy and the car sounds like it's going putt putt putt putt. once i get the rpms up a little bit, even just a couple hundred, the car runs just fine.
it threw a CEL as i was driving away from the shop and so went back. it was a p0300 code. he said he inspected all the valves and such when they put the timing belt back, to make sure there wasn't damage due to the timing belt slipping, and there was no valve damage (thankfully).
so what gives?! something happened between them fixing it and me getting the car back. no more crazy engine noise and hesitations from tensioner, but now i have a really really bad idle!
i found this:
If you have a scan tool, look at the Short Term Fuel Trim (STFT) and Long Term Fuel Trim (LTFT) values. Normal range is plus or minus 8. If the numbers are +10 or higher for STFT and LTFT, the engine is running LEAN. If you rev the engine to 1500 to 2000 rpm and hold it for a minute or so, and the STFT value drops back down to a more normal reading, it confirms the engine has a vacuum leak at idle. If the STFT value does not change much, the lean fuel condition is more likely a fuel delivery problem (weak fuel pump, restricted fuel filter, dirty fuel injectors or a leaky fuel pressure regulator) than a vacuum leak.
so i slapped on my scan tool, and if the above is correct, then i have a vacuum leak somewhere. my STFT is +/-2% or less most of the time if i'm about 1k-1.5k rpm. i'm they didn't close up a seal or messed up a hose.
does anyone know what's involved in replacing/fixing timing belt that involves the vacuum system?
If you have a scan tool, look at the Short Term Fuel Trim (STFT) and Long Term Fuel Trim (LTFT) values. Normal range is plus or minus 8. If the numbers are +10 or higher for STFT and LTFT, the engine is running LEAN. If you rev the engine to 1500 to 2000 rpm and hold it for a minute or so, and the STFT value drops back down to a more normal reading, it confirms the engine has a vacuum leak at idle. If the STFT value does not change much, the lean fuel condition is more likely a fuel delivery problem (weak fuel pump, restricted fuel filter, dirty fuel injectors or a leaky fuel pressure regulator) than a vacuum leak.
so i slapped on my scan tool, and if the above is correct, then i have a vacuum leak somewhere. my STFT is +/-2% or less most of the time if i'm about 1k-1.5k rpm. i'm they didn't close up a seal or messed up a hose.
does anyone know what's involved in replacing/fixing timing belt that involves the vacuum system?
so the shop called me and told me what they found. values on cylinder 2 and 4 are very slightly bent...so it's causing a vacuum leak on low rpms but is small enough that at high rpms there's no issues.
cost to fix, about 1.5k =(
this is so strange. before the timing belt tensioner fix, there was the hesitation but no issues w/ idle. now they fix the timing and the valves are bent? wtf =(
he's gonna try to advance the timing to where he found it to see if that'll fix the issue. i wonder if the knock will come back if he advances the timing....
my poor p5...and wallet....
cost to fix, about 1.5k =(
this is so strange. before the timing belt tensioner fix, there was the hesitation but no issues w/ idle. now they fix the timing and the valves are bent? wtf =(
he's gonna try to advance the timing to where he found it to see if that'll fix the issue. i wonder if the knock will come back if he advances the timing....
my poor p5...and wallet....
the_mgroove
Member
Speaking of this topic, this happened to my car this morning.
Please read my post: http://www.mazdas247.com/forum/showthread.php?t=123762964
The CEL light came on after 1 day being fixed by my mechanic. He checked out everything and it was fine. Now it comes on and at low RPM, it vibrates a bit while at full stop/low speed. Should this be checked out? Or can I go about holding it for a few days until I'm able to drop it off at the mechanic. Please help!
Please read my post: http://www.mazdas247.com/forum/showthread.php?t=123762964
The CEL light came on after 1 day being fixed by my mechanic. He checked out everything and it was fine. Now it comes on and at low RPM, it vibrates a bit while at full stop/low speed. Should this be checked out? Or can I go about holding it for a few days until I'm able to drop it off at the mechanic. Please help!
Yes, take it back to the same mechanic if they are planning to re-evaluate it without charging another diagnostic fee. When they read the OBD codes, compare it with the previous read-out results, and post them here. I'm curious if the same trouble codes have returned or if it's a whole new set of codes.
Hello, btw. This is my first posting. I've been just lurking on here.
Hello, btw. This is my first posting. I've been just lurking on here.
Im lurking too - second post
I have a similar issue, PO0401 is the code i get. I am getting new coils and wires today, have replaced the plugs and will be dealing with EGR last... its too damn cold to get that out just yet!
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