no start after spark plug change
09-04-13, 12:31 PM
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no start after spark plug change
Hey all, I just recently changed the spark plugs with factory plugs, put everything back together. I also made sure hoses were connected and when I tried to start the car it would crank for about 5 seconds but not start. I have no clue what it could be. I jumper cables onto another car just in case the battery was weak, but nothing. Here are a few things I did:
1. Cleaned the throttle body, intake valves, and the surge tank with carb cleaner. Hopefully this did not mess anything up.
2. replaced surge tank gaskets and throttle body gasket
3. After the first time I tried starting it, I noticed a ground cable bracket to the abs brake box was not connected to one of the bolts on the surge tank. But after connecting it, still nothing.
4. I also think the coil packs aren't touching the tip of the spark plug.. maybe this could be the issue. I'll look into this when I get home
5. no fuses are blown
6. I removed the spark plugs to see if it was leaking with fuel and I could smell just a bit but it didn't look like it was flooded with fuel with the amount of times I tried starting it.
7. Fuel pump seems to be working, I could hear the pump when I press the start button without pressing the brakes.
8. I also removed that fuel line to see if maybe it wasn't connected correctly and when I removed it fuel spat out, like there was a lot of pressure in it.
Any thing I should look out for? I plan on taking everything apart again after checking to see if the coilpacks are connected to the spark plugs.
1. Cleaned the throttle body, intake valves, and the surge tank with carb cleaner. Hopefully this did not mess anything up.
2. replaced surge tank gaskets and throttle body gasket
3. After the first time I tried starting it, I noticed a ground cable bracket to the abs brake box was not connected to one of the bolts on the surge tank. But after connecting it, still nothing.
4. I also think the coil packs aren't touching the tip of the spark plug.. maybe this could be the issue. I'll look into this when I get home
5. no fuses are blown
6. I removed the spark plugs to see if it was leaking with fuel and I could smell just a bit but it didn't look like it was flooded with fuel with the amount of times I tried starting it.
7. Fuel pump seems to be working, I could hear the pump when I press the start button without pressing the brakes.
8. I also removed that fuel line to see if maybe it wasn't connected correctly and when I removed it fuel spat out, like there was a lot of pressure in it.
Any thing I should look out for? I plan on taking everything apart again after checking to see if the coilpacks are connected to the spark plugs.
09-04-13, 01:14 PM
#2
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I would say the coil packs are not producing spark to the spark plug to start so check that first because it could mean that you have the wrong spark plugs for the car. did you check if they were different lengths when you compared old plugs to new?
09-04-13, 01:19 PM
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I thought I did, but then again I'll check them again.. I remember for sure I checked the markings (model #) on the spark plugs and they matched perfectly.
09-04-13, 02:12 PM
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Do you have a code scanner or techstream cable?
It's possible all the coils are not correctly fitted, but I would have thought unlikely that all of them are. The original denso coils fit very loosely on the plugs; it feels like they aren't touching, but if you bolt them down, they should be correctly positioned. I did replace one with an aftermarket as part of fault finding before doing the plugs, and it bites the top of the plug like a pitbull.
Unless all of the plugs were not connected, I'd expect the system to at least attempt to fire and run badly.
About not seeing flooding, this isn't necessarily reliable. The Denso ECU will disable fuel injection to a cylinder if the coil doesn't send back a timely spark confirmation signal. If a coil isn't correctly connected to the car's wiring harness, no fuel will be injected.
It would be worth checking that the harness isn't damaged, and that you get a good ground and 12V to each coil. The two outer edge pins on teh coil connector are ground and 12V (can't remember which way round, sorry). The inner 2 are fire and confirmation signals.
Did you remember to reconnect the 2 swirl flap connectors? These are the 2 wires behind the surge tank.
Are all the vaccuum hoses and inakes correctly installed. The Denso ECU will not start the engine if the MAF sensor is not in the intake air stream.
It's possible all the coils are not correctly fitted, but I would have thought unlikely that all of them are. The original denso coils fit very loosely on the plugs; it feels like they aren't touching, but if you bolt them down, they should be correctly positioned. I did replace one with an aftermarket as part of fault finding before doing the plugs, and it bites the top of the plug like a pitbull.
Unless all of the plugs were not connected, I'd expect the system to at least attempt to fire and run badly.
About not seeing flooding, this isn't necessarily reliable. The Denso ECU will disable fuel injection to a cylinder if the coil doesn't send back a timely spark confirmation signal. If a coil isn't correctly connected to the car's wiring harness, no fuel will be injected.
It would be worth checking that the harness isn't damaged, and that you get a good ground and 12V to each coil. The two outer edge pins on teh coil connector are ground and 12V (can't remember which way round, sorry). The inner 2 are fire and confirmation signals.
Did you remember to reconnect the 2 swirl flap connectors? These are the 2 wires behind the surge tank.
Are all the vaccuum hoses and inakes correctly installed. The Denso ECU will not start the engine if the MAF sensor is not in the intake air stream.
09-04-13, 02:32 PM
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Thanks,
I believe the two wires that I disconnected and then reconnected was the one that connects to a big yellow piece (swirl flap motor?) and the one that connects under the fuel line piece. I'll check the hose that connects to the surge tank thats next to the firewall to see if there is a connection problem there. intake is correctly installed. If I still can't find anything I'll take the surge tank out once more and recheck everything.
I believe the two wires that I disconnected and then reconnected was the one that connects to a big yellow piece (swirl flap motor?) and the one that connects under the fuel line piece. I'll check the hose that connects to the surge tank thats next to the firewall to see if there is a connection problem there. intake is correctly installed. If I still can't find anything I'll take the surge tank out once more and recheck everything.
09-04-13, 10:31 PM
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aight after taking everything apart again I noticed a few things...
1. I shined a light inside where the valves are and noticed lots of gunk on a few of the valves.. probably from spraying the carb cleaner and it all built up on top of the valves.. Also I went on vacation the first time I put everything back together and never tried starting the car because I was missing a bolt. I wonder if the carbon deposits got so heavy its causing sticky valves?
2. After checking each and every spark plug I noticed 3 of them were fouled with large deposits of carbon stuff on them. Again, maybe from the carbon deposits that were sprayed down into the valves.
3. I also sprayed carbon cleaner in the surge tank and lots of dirty black liquids came out.
I probably should have just sprayed seafoam into the vacuum line while the engine was running in small amounts rather than cleaning everything while taken apart and not starting the car after 4 days.
Do you guys have any suggestions on cleaning the gunk out? I also replaced the spark plugs that were full of carbon deposits and the car still doesnt start. It wouldnt surprise me if there is gunk on the spark plugs again.
I'll also have to check spark from the plugs just to make sure ignition coils are still good.
1. I shined a light inside where the valves are and noticed lots of gunk on a few of the valves.. probably from spraying the carb cleaner and it all built up on top of the valves.. Also I went on vacation the first time I put everything back together and never tried starting the car because I was missing a bolt. I wonder if the carbon deposits got so heavy its causing sticky valves?
2. After checking each and every spark plug I noticed 3 of them were fouled with large deposits of carbon stuff on them. Again, maybe from the carbon deposits that were sprayed down into the valves.
3. I also sprayed carbon cleaner in the surge tank and lots of dirty black liquids came out.
I probably should have just sprayed seafoam into the vacuum line while the engine was running in small amounts rather than cleaning everything while taken apart and not starting the car after 4 days.
Do you guys have any suggestions on cleaning the gunk out? I also replaced the spark plugs that were full of carbon deposits and the car still doesnt start. It wouldnt surprise me if there is gunk on the spark plugs again.
I'll also have to check spark from the plugs just to make sure ignition coils are still good.
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09-05-13, 07:02 AM
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found online someone who did the same thing I did, where gunk just formed in the cylinders causing the car to crank but not turn over and start.. they took it to a mechanic and he put some type of solvent in and cleaned out the spark plugs and gunk in the cylinders and the car started up perfect. He said something about gunk causing fuel not to flow to the spark plugs..
Just wondering if you guys know what type of solvent I could use to clean out this gunk. and could I just clean it out from the head where the valves are and the spark plug holes that lead to the cylinder?
If this does work, I highly suggest not spraying carb cleaner or any type of cleaner to clean out the surge tank and manifold area while the car is not running.
Just wondering if you guys know what type of solvent I could use to clean out this gunk. and could I just clean it out from the head where the valves are and the spark plug holes that lead to the cylinder?
If this does work, I highly suggest not spraying carb cleaner or any type of cleaner to clean out the surge tank and manifold area while the car is not running.
09-05-13, 09:02 AM
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thanks. I'll try that.. So just remove all spark plugs, would the intake manifold still need to be installed? and just run some wires from the terminals of the starter and connect to battery for a few seconds to turn the motor?
I was also thinking of pulling out the air compressor and blowing some air in the spark plug holes and sticking a long tube in there to hopefully vacuum some of the deposits. going to be doing this with the top of the intake valves. I also probably will clean the spark plugs with brake cleaner as well since they are still new.
I was also thinking of pulling out the air compressor and blowing some air in the spark plug holes and sticking a long tube in there to hopefully vacuum some of the deposits. going to be doing this with the top of the intake valves. I also probably will clean the spark plugs with brake cleaner as well since they are still new.
09-07-13, 10:32 AM
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anyone know where this cable connects to? It looks like a ground.. I saw it after pulling my battery out to recharge..It's right under the throttle body next to the battery positive terminal. I don't remember disconnecting this..
09-10-13, 12:51 PM
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yep it looked like there was a bolt missing on a spot on the valve cover/head. So I hooked it up there and still no go.. I took apart the intake manifold cleaned it up and cleaned up more carbon deposits on top of the valves with a vacuum and carb cleaner and check one side of the injectors. The injectors had some carb deposits around the edge but not on the tip where the fuel spits out.. I also checked the compression on all 6 cylinders with the intake manifold off.. I noticed when the engine was cranking it seemed to crank pretty slow. compression on all 6 cylinders were really low, like around 45 to 50 psi, so not sure if I was checking compression right or not. I had triple A tow it to a shop.
next day I get a call and it starts.. they said the maf sensor was really dirty so they cleaned it up and it starts fine.. I have no idea how the maf sensor got so dirty and caused it not to start, when before the spark plug change it started perfectly..
I know the gap on the old plugs were around 1.2 to 1.3 mm while the new ones were at about 1.1mm. maybe the maf sensor would work with the 1.2 - 1.3mm gapped plugs.. no idea. or maybe maf sensor messed with my timing somehow? oh well.. it works now.
next day I get a call and it starts.. they said the maf sensor was really dirty so they cleaned it up and it starts fine.. I have no idea how the maf sensor got so dirty and caused it not to start, when before the spark plug change it started perfectly..
I know the gap on the old plugs were around 1.2 to 1.3 mm while the new ones were at about 1.1mm. maybe the maf sensor would work with the 1.2 - 1.3mm gapped plugs.. no idea. or maybe maf sensor messed with my timing somehow? oh well.. it works now.
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