afterfire and hesitation
- Thread starter 885.0conv
- Start date
liljoe07
5 Year Member
Id pull the valve passenger side valve cover, and check the Adjusting nut and see if its loose. Sometimes they back off a little bit. May need to check all them on that side, it really hard to tell exactly which one it is.
I finally got the plugs changed to the autolites and after hooking the wires back up the ticking is gone. I also changed the plenum gasket on the upper intake. I noticed that there was a lot of oil sitting in the plenum which is probably why the plugs were coated with oil when I pulled them. I am pretty sure that there is not supposed to be oil there. (I changed the pcv valve and clean the "sos pad" about 6-9 months ago on 4k miles.) After doing that my afterfire is gone but I still have the hesitation til 3-3.5k under WOT. Under normal driving the car is fine. At idle there is a big gas smell and there is a lope. I changed a lot of the vacuum lines that were hard with some silcone ones but didn't help me. I am going to install the fuel pressure gauge I got and see what I have. Was it 40 psi with the vacuum line off the reg. and 32 pis with it on? I get no codes except the 11 but when I am driving the check engine will come on for a second then go away. I think it is in the 10 pin connector because that was causing the 5V break going to the EGR. Any other suggestion besides changing the rest of the vaccum lines?
liljoe07
5 Year Member
Run the codes while the engine is running. Looks like you are only doing the Engine Off test.
With an intermittent Check Engine Light, it should have stored the codes in Continuous Memory. Which is after the Engine Off codes have flashed twice. Also once the Engine running codes are done cycling twice, do a brief Wide Open Throttle and the Cylinder Balance test will start. It will also flash codes too.
With an intermittent Check Engine Light, it should have stored the codes in Continuous Memory. Which is after the Engine Off codes have flashed twice. Also once the Engine running codes are done cycling twice, do a brief Wide Open Throttle and the Cylinder Balance test will start. It will also flash codes too.
Ok I got the fuel pressure gauge in and I get 40 psi with the reg. vac off, 39 psi with it on and 30 psi when the cylinder balance test is going.
I checked the codes and got 31 (probably the short in the wire) and 66 (disconnected maf to test).
I dumped the codes and got
11 (KOEO)
21 (KOER)
99 (With the first cylinder balance test)
72 (With the second balance test).
I noticed that when the MAF sensor is disconnected the engine idles the same way. So I changed it with another one I have though it is probably bad because the afterfire came back.
I checked the codes and got 31 (probably the short in the wire) and 66 (disconnected maf to test).
I dumped the codes and got
11 (KOEO)
21 (KOER)
99 (With the first cylinder balance test)
72 (With the second balance test).
I noticed that when the MAF sensor is disconnected the engine idles the same way. So I changed it with another one I have though it is probably bad because the afterfire came back.
liljoe07
5 Year Member
Those would be the cylinders to focus on. But first try and clean the 10 pin connectors behind the intake. Then if those cylinders are still showing up on the CBT, check those injectors with a test light and make sure they are firing.
liljoe07
5 Year Member
Well the major problem may have presented itself. The check engine light came on so I ran the codes. I got 31 with KOEO so check wires and saw that the 5 vref on the 10 pin connectors would come and go. I saw that one fix is to spread the male contacts and push the female ones in. Well I did that now the car will not start so I cant run the KOER codes. It will crank but not turn over even when stepping on the gas. You can hear that it is trying and will start for a split second and then just die. I have seen jr got a crank but no start guide so I guess I will start there.
liljoe07
5 Year Member
Since you messed with those 10pin, take them back apart and make sure you didnt push a PIN through the connector. It happens.
Ok, checked the 10-pin connectors and they were fine. Started the car and it fired up, noticed that the idle went high around 1k, checked the timing (it was at 10 degrees) thought it might help to bump it to 14. I turned the car off to loose the dis and when I went to turn the car back on the car would not start just crank. Check the cap and rotor and there was a good amount of carbon build up so I clean both of them. Checked the rotor at TDC and it was at the first cylinder but car would not start.
After looking at the "crank no start thread" I decided to change the ECT and ACT sensors. After doing that the car starts fine when it is warm, there was a lot oil on the ACT sensor could have been giving a false reading. I bumped the timing up to 14. I moved the plug wires around and all I get on the cylinder balance test was three. I made sure that three's wire was plugged in. When I ran the cylinder balance again I kept getting different numbers. The first one was three, then 7,2 then 5,1 so I don't know which cylinder to look at now. The car sounds better at idle. I am wondering if with my combo I don't start making power til 3K. I order some different plug wires because I noticed that two of the wire were arcing to the engine.
I finally got to look at my car. I did find that a lot of the rocker arm studs were loose 12 of the 16 to be exact. So I torqued all the studs to 55 ft/lbs with blue loctite and reset valve lash. The ticking sounds has gone completely away sounds nice for once. I was wondering can after fire be caused by not getting enough fuel pressure at WOT.
liljoe07
5 Year Member
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