Has to be something electrical.
Replaced spark plugs and car won't run?
- Thread starter pbm
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Maybe someone pulled the old banana in the tailpipe routine on you? Axel Foley says to check for that.
I'm unclear if this only applies to turbos -- and if the vehicle in question is a turbo....but were these two hoses reattached?
Your symptoms could absolutely be a massive vac leak and/or MAF problem, but it looks like you don't unplug the MAF for this job
Your symptoms could absolutely be a massive vac leak and/or MAF problem, but it looks like you don't unplug the MAF for this job
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Occams Razor says......
It most likely has something to do with the plug wires. You may have damaged them (old and brittle?) or they are not installed in the correct positions. You did check the gaps before installing, didn't you?
OR....you inadvertently disconnected a sensor connection somewhere while doing all the other stuff. It's something electrical either directly related to the plugs/plug wires/coil packs....or a sensor disconnected.
It "should have nothing to do with the brakes. Deep breath....carefully inspect everything you touched or were near during the process with a light and glasses if necessary. Read any codes.
A "well I'll be ****ed" moment is just ahead.
It most likely has something to do with the plug wires. You may have damaged them (old and brittle?) or they are not installed in the correct positions. You did check the gaps before installing, didn't you?
OR....you inadvertently disconnected a sensor connection somewhere while doing all the other stuff. It's something electrical either directly related to the plugs/plug wires/coil packs....or a sensor disconnected.
It "should have nothing to do with the brakes. Deep breath....carefully inspect everything you touched or were near during the process with a light and glasses if necessary. Read any codes.
A "well I'll be ****ed" moment is just ahead.
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Stay with the OE and part number of spark plug
All that extra crap is only on the turbo variants and there's enough slack in everything there that you don't have to detach anything. Some people do, especially the (2) hoses you refer to, to give clearer access to the #4 plug.
And correct on the MAF. It doesn't need to be touched for this.
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The only time I ever changed the plugs and the car would not start was way back in the 80's. I somehow got my plug wires reversed.
That was long before cell phone, face time and Google. I had to call my buddy who also had a Datsun 280z and he drove over so I could look at his wires and yes somehow I had reversed my plug wires!
I guess with coil pack on plugs, spark plug wires that can EZ reverse are now a thing of the past,,, My Harley still has wires. All that said no way to mix up coil packs I guess?
Best of luck OP...
That was long before cell phone, face time and Google. I had to call my buddy who also had a Datsun 280z and he drove over so I could look at his wires and yes somehow I had reversed my plug wires!
I guess with coil pack on plugs, spark plug wires that can EZ reverse are now a thing of the past,,, My Harley still has wires. All that said no way to mix up coil packs I guess?
Best of luck OP...
Same thing happened to me with my El Camino almost 30 years ago /
Never crossed my mind that I could've done anything wrong with the wires....
Rule out the obvious things first:
1) Did you reversed some plug wires
2) Did you connect things back correctly
3) Did you buy the right plugs / did the old plugs work if you put them back in
4) Did you do anything else that can cause starting issue like drain the battery or disconnect a sensor, disconnected the injector or throttle, etc.
5) Code?
6) Did you break anything mechanically
Most likely one of the above. Even fake plugs should at least start and idle.
1) Did you reversed some plug wires
2) Did you connect things back correctly
3) Did you buy the right plugs / did the old plugs work if you put them back in
4) Did you do anything else that can cause starting issue like drain the battery or disconnect a sensor, disconnected the injector or throttle, etc.
5) Code?
6) Did you break anything mechanically
Most likely one of the above. Even fake plugs should at least start and idle.
On the cars I've seen, no. The wiring harnesses are only long enough to reach their specific coil pack.
I agree the boots are tight and the engine is tilted to the rear a little making it a bit more difficult to get the boots back on.
I took off all 4 coil packs to check for the springs which were present on every one of them. While I had them off I took out the Autolites and reinstalled the NGKs and was surprised that the Autolites had blackish deposits (running rich) considering it only went about a mile on them. I reinstalled the coils carefully and cleaned the Throttle body as suggested on here. The car started with some stumbling but soon smoothed out and I let it idle for about 6 to 7 minutes to get up to temperature. I drove gently (as suggested on YT after an ECU cleanse) for about 10 miles and it ran well except that it threw a 'check engine' light near the end of the drive (drivability didn't change so I'm hoping the code was residual from the earlier issue). I erased the code and hope my trouble is over. I foolishly didn't note the code # but it may have said 'no code' and had stored codes...I can't remember.
Now you are really confusing us! Earlier, you said the new plugs were NGK Rutheniums, but now you are indicating they are Autolites???
"...Yesterday I went out when the engine was cold and replaced the OE spark plugs with new NGK Rutheniums and then proceeded to replace the rear brake pads after putting the e-brake in 'maintenance mode'."
Autolites often run poorly in some Asian cars and I only install NGK or DENSO plugs in them.
See post #13. I put the NGKs at first and then tried Autolites...
I am sorry, your hypothesis does not sound plausible to me. There is something more going on there that has nothing to do with ECU settings on basically clearing of common "adaptives". Your last comment makes more sense, or you pulled a wire out of a sensor/coil/ect.. by moving stuff around.
My experience says otherwise with both an '01 RAV4 and '09 Taco 2.7. The former wouldn't even run initially and the ONLY thing that was done was battery replacement. The latter would take excessive cranking and sometimes stall.
It would seem Toyotas are particularly capable of adjusting throttle trim more than other makes (assuming a caked throttle body) OR the baseline programming is assuming near-unrealistic conditions even if the throttle body was clean in my examples (unlikely).
I've also had my '07 F150 4.6 randomly die at stoplights for a whole day after power was removed.
YMMV, but I know what I've seen (shrug)
DId you use anti-seize?? If anti-seize got on your fingers and you transfered that to the spark plug towers( porcelain) and the coil boots, you may have tracks and its shorting out. Anti-seize is very conductive.
Counterfeit plugs are also a thing, unfortunately
