[EW7153]

I followed the instructions for changing the spark plugs on the 2.7 V6 that are posted on the hyundaimods site. All seemed to go well apart from it being **** tight between the engine and the firewall and very fiddly getting the bolts out and back in.
On starting the car it backfires through the throttle body and runs rough and dies. It seems to me that it is not getting enough fuel. I have triple checked that all electrical connectors and vacuum hoses are back where they came from.
I can only think that perhaps a wire may have been broken to a sensor or solenoid but pinpointing where exactly the problem is is difficult.

I read a topic on the sonata forum where someone had similar symptoms after rebuilding their heads on their 2.7 V6 and eventually worked out that he had the connectors to the throttle body reversed.
I only had 2 of the 3 connector plugs disconnected and they can't be reversed, they only fit one way.

All the plug leads where disconnected one at a time and only one had to be disconnected from the 'distributor' so they are all back in the right order.

Can anyone offer any help or solutions?

Cheers Bruce

 

[newbuyer]

you put the wires on in the wrong order..... here's the firing order, try again.

http://autorepair.about.com/library/firing.../bl-fo-0296.htm

 

[EW7153]

Hi Gweedo, the symptoms would suggest so BUT I only removed one plug cap at a time and changed the plug and replaced the cap. Also the leads are tailored length and physically cant go on to the wrong plug. I also only removed the one plug lead from the distributor for the number 6 cylinder because it is so short that you have to to get it out of the deep plug seat. So I am 200% sure that they are where they were when I started.

I have checked all the ECU fuses and they are all okay.

 

[newbuyer]

QUOTE (EW7153 @ Jun 19 2010, 10:49 PM) index.php?act=findpost&pid=334550

Hi Gweedo, the symptoms would suggest so BUT I only removed one plug cap at a time and changed the plug and replaced the cap. Also the leads are tailored length and physically cant go on to the wrong plug. I also only removed the one plug lead from the distributor for the number 6 cylinder because it is so short that you have to to get it out of the deep plug seat. So I am 200% sure that they are where they were when I started.

I have checked all the ECU fuses and they are all okay.

Well, it's gotta be something you did, because it ran fine before you touched it.

Did you mess with the timing?

 

[peter9505]

Could it be that the sparkplugs were not set to the correct gap ???

 

[jsinton]

QUOTE (peter9505 @ Jun 20 2010, 02:42 PM) index.php?act=findpost&pid=334686

Could it be that the sparkplugs were not set to the correct gap ???

Chances are it would still run, just not to spec.

 

[homerdog]

QUOTE (jsinton @ Jun 20 2010, 03:06 PM) index.php?act=findpost&pid=334694

Chances are it would still run, just not to spec.

if it's backfiring, ie farting in the intake, then you've moved the timing somehow. the only thing I can think of is that there's a sensor been moved or clobbered as you were doing things. my old merc 270k and counting does this but, it has a dizzy!! h

 

[peter9505]

EW7153, I am curious to hear if you`ve solved the problem. Was it a sensor if so which one??? :whistling:

 

[gazza!!!]

Did you remove the distributer cap have you replaced it 180 degrees out? dead easy to do and would give exactly the symptoms you describe!.

Gazza!!!

 

[sbr711]

QUOTE (gazza!!! @ Jun 27 2010, 12:41 PM) index.php?act=findpost&pid=336536

Did you remove the distributer cap have you replaced it 180 degrees out? dead easy to do and would give exactly the symptoms you describe!.

Gazza!!!

No distributor on USA/Canada models

 

[jsinton]

If you are sure the plug wires are on correctly, then the next thing to check is did you get the intake back on correctly so that it's not sucking in air where it's not supposed to. It could be a big intake air leak.

 

[EW7153]

Turned out that despite appearances the plenum was not back on correctly resulting in an air leak.
I felt like a complete idiot but it seems it is an easy mistake to make.
The rear bolts under the surge tank are replaced by feel as you can't see them and they also hold the sensor and fuel pipe brackets.
They were screwed it but sitting on top of the bracket not through the holes.

At least I found it myself with the help of some mates. I heard of an mechanic that did the same thing to a clients Santa Fe and had to send it to the dealer to get it fixed! How embarrasing.

Thanks for all the suggestions.

 

[lovemysantafe]

Glad you were able to get it fixed without much drama. :thumbsup:

 

[peter9505]

It happens to the best , thanks for the honest response. Now forum users will have an in if it happens to them.