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okay i'll start off by saying whats up to everyone. I have a s13 with a rb20 in it, and if runs like shit. I blew the headgasket last fall and over the winter i did a little build up on it.

Head gasket

ported head

10.2 lift kelford cams with springs

hks low mount

60-1

hks wastegate

custom front facing intake manifold

q45 tb

fmic

Grand national coil conversion

aeromotive fuel regulator

Now for the problem

hard starting problem-no matter how long i crank it over it wont start until i give it some throttle

Idles really low or really high- Seems to get worse when you warm it up

sputtering or surging problem- I think the GN coil conversion fixed that, i havnt drove the car long enough since.

Feels like my timing is off

I have checked for boost and vac leaks, tps adjustment, took apart my iacv, messed with timing

If i adjust me tps to .40 or anywhere with the idle switch engaged it idles really low and hunts, also when ever my e-fans kick on it kills the engine. if i adjust to where the idle switch isnt engaged then it wont die when the fans kick on but it will idle a little high.

When i took the iac valve apart it was pretty clean put the spring seemed weak. It pushed the valve closed but i could move it a little further with a screw driver.

When i adjust my timing it jumps around, If i set it in the middle and then put a timing light on it is past all the marks on the crank pulley. I live in the u.s.a. so i cant take it to any shop to have it fixed. I know a lot about cars but this doesnt make any sense to me. I thought it could be because the alternator wasnt putting out amps to push to efans but i upgraded it to a nissan quest 110 amp alt and it still does the same thing.

thanks

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and what are you using to tune the car with??

start with clean AFM, Spark plug gap 0.8mm. Wouldnt 10.2 lift cams required a lifter change as well..(not sure about that)

What turbo? what PSI?

What Air fuel ratio

have you dynoed it to see whats going on,

compression tested??

Did it ever run right??

checked intercooler pipes for leaks?

Edited by race_snooze

If you blew a head gasket, did you check that the head was still flat?

Have you checked compression? What ECU are you running?

There are 2 parts to the TPS - Switch and Sensor. Adjust the Switch to control idle (tells the ECU throttle has closed).

Big lift cams probably wouldn't be helping matters at all.

So far im running a stock comuter and injectors but im just trying to get the damn thing to run idle decent before i spend more money on something that isnt going to fix the problem.

i put new plugs gapped to .8mm allread

I took the head into the machine shop they check it for crackes and warpage. They had to maching out the around the lobes so it would clear. I put the right kelford springs to go in i wasnt told anything about changing the lifters out. ???

Im running a 60-1 turbo. .63 turbine and .70 compressor Hks 50mm wastegate on a 10 psi spring.

Im waiting for my wideband to show up. i dont want to dyno it yet until i get a gold tune and atleast make it street friendly.

I will do a compression test again. I havnt been able to get it to run right since i put all of this stuff on the car.

I have built two leak tester and checked it all the way up to 10-15 psi with only tiny buddles around the the welds but nothing major. and around the iacv valve but i put a new gasket on it and was fine.

I know that there are two parts to a tps when i adjust it to when the idle switch is on it idle really low but when i adjust it to where the idle switch isnt on it idles really high.

My coils were fried so instead of buying a new set i ran a wasted spark setup by taking a Grand national coil pack and wires. l_d8d710e70841348ac850f2b2ecb3d61f.jpg

The wires arnt installed in the picture yet but that my ignition setup. It gets everthing away from heat. i put the pick up on the no1 wire right by the plug. I really apriecate your help thanks

Edited by mott6904

Stock Computer & Injectors ??? Im surprised it starts at all!! I'm definitely no expert but I'd say that would be the major problem...

I'd be investing in a decent ecu & injectors as a minimum...... edit: and a higher flowing fuel pump

And I thought you had to change to solid lifters with cams that big in a 20? I know you do with the 25's....

Your running substancial cams

Bigger Throttle body/plenum

(possibly upped fuel pressure via the FPR)

All on the stock ECU?

I think thats your problem right there mate.

Without giving it justice of a tune to setup and compensate for the massive changes - the stock ECU will be having an absolute fit

yea that is what i was begining to think, since i have to adjust my tps higher to get it to idle decent that is adding more fuel just to make it idle better. I really just dont have the money to spend on this car right know. There is a guy around me that burn eproms for like 120 and he will solder in the board and then do all the updates that is needed. I just need to save up for some good 700-800 cc injectors and also a z32 maf. I will keep you guys posted also if there is anything you can think of then let me know. thanks

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