95 samkick hard cold start

[OffroadRob]

I've got a 88 samurai in the shop giving me an issue.  It had a 95 16v in it and we sent a 97 16v out for a rebuild.  Port and polish the heads, 20 over pistons, 10 shaved off the deck.  The cam has been reground by altered ego motorsports and the 4 degree timing key was installed.  Timing has been set at about 11 degrees.  I'm reusing the original 95 california harness and ecu.  Cold starts take some cranking, pedal pressure makes no difference.  After warming up it'll start right back up easy.  There's a new egr valve, egr temp sensor and new maf.  "Cold air" intake.  Injectors have been re sealed.  Fuel tank and pump are new from petroworks.  Fuel pressure will sometimes not hold at 40 key on, sometimes will drop as soon as the pump shuts off.  Holding or not doesn't matter.  Return line was pinched, and fuel pressure held solid so I don't suspect injector leakage.  IAT, and ECT test good with good voltage.  What should ISC voltage be key on, is it readable?  TPS has been tested and passed.  Throttle body and IAC is off the 97.  The 95 was disassembled for cleaning and the iac rubber gasket deformed so unusable.  Any suggestions?

[fixkick]

I've got a 88 samurai in the shop giving me an issue.  It had a 95 16v in it and we sent a 97 16v out for a rebuild.  Port and polish the heads, 20 over pistons, 10 shaved off the deck.  The cam has been reground by altered ego motorsports and the 4 degree timing key was installed.  Timing has been set at about 11 degrees.  I'm reusing the original 95 california harness and ecu.  Cold starts take some cranking, pedal pressure makes no difference.  After warming up it'll start right back up easy.  There's a new egr valve, egr temp sensor and new maf.  "Cold air" intake.  Injectors have been re sealed.  Fuel tank and pump are new from petroworks.  Fuel pressure will sometimes not hold at 40 key on, sometimes will drop as soon as the pump shuts off.  Holding or not doesn't matter.  Return line was pinched, and fuel pressure held solid (to what?) so I don't suspect injector leakage. That means the FPR leaks.(clear as day)

  IAT, and ECT test good with good voltage.  What should ISC voltage be key on, is it readable?  ISC only works running hot, IAC is thermal and only below 105F water temps.
ISC is 200 pulse per second and duty cycle sets idle hot only.and is a PWM device, not DC .

cold starts get AIR from iAT, only and if missing will flood lack of air, or injections are weak. (FPR)

TPS has been tested and passed.  Throttle body and IAC is off the 97.  The 95 was disassembled for cleaning and the iac rubber gasket deformed so unusable.  Any suggestions?

this engine running 95 manifolds and TB ????? CUSTOM engine are not simple at all what matters are all parts there, not just long block)

what maf, 99% off all MAFs sold are crap,  not real and from china called knockoffs pure crap,
the side sticker on all real MAFs tell you it is authentic.  I have photos of real....  best is rebuilt from CARDONE ONE. for sure. not from ebay at $15 ever.
95 ECU right? 16v sure.
but the MAF is super key part, to run right, as is fuel pressure and FPR runs that and must be correct FPR too.
key on   only runs the pump for 3seconds,(primes purges air in lines only)so key on pressures after 3 times key'd is best and will leak down in 1 minute . next it fuel pressure idling.  6; PSI less pressure at idle , that keyon max, must be.  Use  real FPR that does not leak is best, and regulates at all plenum vacuums.


dropS fast fuel pressure meanS FPR IS bad or 1 of 4 injectors leak like mad, after all injectors are OFF in 1/1000th of a second after key off.
BUT BLOCK RETURN LINE DOES NOT PROVE INJECTOR ARE GOOD. ONLY BENCH TESTING THE FPR TO SEE IF IT LEAKS PROVES THIS.
THE FPR SET INJECTOR PRESSURE AT ALL TIMES AND ALL VACUUMS.
THE BLOCKED FUEL RETURN Should be 55 to 60PSI this is the pumps max head  or shunt rating. and proves only the pump is not dead, or weak .
FPR is bad. is easy to test benched, for vacuum leak the leaks from fuel input to fuel output nipples, FPR is closed benched no vac.

cloned maf are shit.

rebuilt MAf'S are good, if from real sources and not from china.

that is all I can think of so for.

I hate cold air done wrong, most are, most are hot filthy air down grade.  the right way is to steal air from the cowling air box, that the wiper motor hides in, this is turbo mode fast.
and clean air there. and never hot.  
most cold air kits beat the MAF to death bouncing a $1200 part as Suzuki real.  why beat that to death I say. if true.


good luck with your build , sorry for my opinions, only that, unseen and untouched.

[OffroadRob]

fuel pressure running is 35.  I bought this maf from amazon https://www.amazon.com/dp/B00YWCVHHW?psc...ct_details  I've had good luck with walker products in the past and no one else seemed to have one.  The air intake set up was built more out of necessity.  The air box that was in there was an all hacked up tracker box that was just resting in there.  I bench tested the FPR that I had in there originally and it blows right through with regulated air, even saw some fuel spit out the vacuum side.  I'm going to pull of the one that's installed and i'm assuming to see the same result.

https://drive.google.com/file/d/1OczqPII...sp=sharing

[fixkick]

that walker I think is true good and rebuilt. nice pick I think

fuel must not ever flow to the vacuum nipple
with that diaphragm inside cracked fuel pressure will be CHAOS and hopeless.

the main valve inside the FPR is closed with huge spring, no vacuum,
the key on pressure does cause the FPR to open and regulate at
spec
keyon (3 times 36 to 43psi) (zero vacuum test) you got 40. so should drop to 34(6psi drop)
idle pressure drops by 6 psi
to ,30 to 37pSI. range.

so key on is 36 then it goes to 30 idle. see?

and PSI does NOT BOUNCe unless you gun the throttle and if you do the vacuum goes near keyon pressure but not that far, as WOT is not 0zero vacuum.

so Engine runs badly hot? (180f normaL) and full WOT power.
or just cold fails , only.?\\\


bad FPR even sticks inside driving driver batty.
as will bad diaphragm.
that bad, the vacuum hose is not AUX fuel injector gone WILD sucking tons of excess fuel.

[OffroadRob]

fuel pressure is about 32 at idle. Engine runs great when hot. It's only the cold start where it struggles to start, once it starts it's fine. Idles up to 2k, slowly drops to about 800. I swapped throttle body and iac assembly from original motor with no luck.