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Car Wont Start

1080 Views 36 Replies 9 Participants Last post by  KB240SR
I installed HKS Step 1 Cams, 550cc Injectors, Z32 MAF, and Enthalpy ECU all done together. Im having the trouble of the car cranking but not starting. It has fuel and spark. Im thinking im having trouble with the timing. When i installed the Cams, i followed the FSM and the cam sprocket marks were at the position shown in the manual at TDC so i think im good there. I think i might be on the wrong TDC compression stroke for piston 1 to set the CAS. Could i have some advice on how to get TDC of piston 1?
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it should be the 2nd line from the left if your looking down on it. Also the the 2 gold links should line up with the timming marks on the cams.
Your best bet would be to set all that stuff using a degree wheel
everything set correctly today as i redid the timing. As i crank the engine over it acts as it wants to start but wont. I was able to get it to start by applying alot of throttle while starting and all it does is miss very very badly to where as soon as i let off the gas the engine dies. I checked my plugs and there NGK Greddy heat range 8 plugs. All the tips were black too. Im thinking maybe the plugs are totally shot and might go with a heat range of 7. Any other advice?
Make sure your ECU knows what kind of maf you have. If you have an safc you need to setup hot wire. also. check for codes. I am having a similar problem right now. i actually have to kill my fuel pump to get car started. your probably throw a code 21 which is maf. make sure the wiring is correct.
Just go to a parts store and get a cheap set of plugs, see if that works. If not then it seems like it s still somthing in the timing. You could try to play with the cas a lil bit if you wanted.
i do have a SAFC which is set to 2in 2out like it should be with my Enthalpy tune. Checked the sensor and it reads 3.xxx volts. Even if somethings wrong with the MAF the car should still start and idle just not go above 2500rpm, Correct?
Doppleganger77 said:
everything set correctly today as i redid the timing. As i crank the engine over it acts as it wants to start but wont. I was able to get it to start by applying alot of throttle while starting and all it does is miss very very badly to where as soon as i let off the gas the engine dies. I checked my plugs and there NGK Greddy heat range 8 plugs. All the tips were black too. Im thinking maybe the plugs are totally shot and might go with a heat range of 7. Any other advice?
It sounds like you are running rich, I would go with what gtp420 said and make sure that the computer knows how much air is going into the motor. Also what is the manufacturer on those injectors? I have had a lot of problems with RC injector spray patterns, causing them not to start. If the MAF is installed correct try having the injectors tested for leaks and spray pattern quality.
Doppleganger77 said:
i do have a SAFC which is set to 2in 2out like it should be with my Enthalpy tune. Checked the sensor and it reads 3.xxx volts. Even if somethings wrong with the MAF the car should still start and idle just not go above 2500rpm, Correct?
The computer has no other way of knowing how much air is coming in without the signal from the maf. If you run your car and unplug the maf it will die.
It should run with out a mafs, it will run like shit. It seems to me ( but i never work with reprogramed ecus) that the safc thinks that the reprogramed ecu is stock. So it might be dumping more fuel in then it needs.
my enthalpy tune is for Z32 MAF. so i set the SAFC for 2in 2out which is how it should be set for the Z32 MAF. Injectors are from Deatcheworks. they all work. there only 6 months old. im gonna check my wiring for the MAF and go out and buy new plugs today.
Maybe the SAFC and your tune just aren't working together. Have you tried running the car without the SAFC on yet?
I was able to get the car running today. Took the valve cover off and checked the timing marks on the chain with the marks on the Cam Sprockets. Found out the Exhaust Sprocket was off 2 teeth somehow. Realigned the sprocket with the mark on the chain and then i noticed i had a Rocker Arm that came off. Wasnt broke, just came off somehow and sometime i dont know when. Placed the Rocker Arm back in place. Placed the cam in place. Tightened everything down. Set the CAS. Got the valve cover back on then made an attempt to start up. Fired up the first crank. I let it run for about 20 minutes, then decided i wanted to check timing with a light. Turned the engine off, disconnected the TPS, then started the engine and all it did was crank. Tried starting it again this time using the throttle and it started up but wouldnt stay idling unless the throttle was controlling it. So i connected the TPS back in, started it up and it wont start unless using the throttle while cranking. It acts like it wants to die but idles on its own around 750 rpm. Has a very rough idle to it. After idling for a while its smoking white like crazy. Started giving it some gas and smoke just pours out the exhaust and revs very slowly. Revs past 2500rpm. I revved it to 5k rpm and it sounded like it was missing horribly bad and backfired. Vacuum is really weak too. On my boost gauge its reading about .3 bar when it used to be at .7 bar at idle. I know i dont have any boost or vacuum leaks because none were played with while doing the work. Any ideas on the situation?
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im gonna end up doing a compression check to assess the damages. If the compression is low on piston #2 chances are its from the Rocker Arm coming off and fucking over the valves and ill be tearing down the head. Wish me luck.
i did a compression test on the engine and it read:

#1 300+ psi (300psi gauge hit the stopper)
#2 145 psi
#3 145 psi
#4 150 psi

Any idea why #1 cylinder is so high in compression? Also while doing the test, a shit load of gas would shoot out the #1 cylinder. All the rest were fine. Even the #2 cylinder were the rocker came off tested fine. Im getting stumped and frusterated with the fucking engine at this point.
Do you want me to come over and take a look at it.
what would you be looking at?
lots of things, rocker arms cams, cam caps , the whole top end , for some reason it seams like all the valves are shut. It could be that you bent the valves. or theres somthin with the rockers and lifters
Have you down a leak down test yet? This will at least tell you if you should really waste your time investigating the valve train. Not knocking enthalpy, but maybe the ECU is bad or not setup properly?
he said he was gettin 300 or 300 plus psi in number 1 cyl.
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