nicholasbartleet

Outline

I have posted several times with this same problem, and thankyou so much to everyone who has helped so far.

Original Thread here

https://www.s2ki.com/forums/index.ph...pic=705995&hl=


Symptoms:

Engine Hunts (Revs Surges) on COLD START
Engine Clicks on COLD START

Symptoms MP3:
http://www.pixelloft.com/car.mp3

Fixes Tried to Date:
*Replaced MAP Sensor
*Replaced TPS
*Tuned TPS with Volt Meter
*Replaced FPR
*Replaced Inlet Manifold Temp Sensor
*Replaced Throttle Body
*Replaced IAC Valve
*replaced VAC Lines
*Disconnected VAC System
*Replaced Secondary Air Injection Valve (back of inlet manifold)
*Replaced Thermostat (because fan was also not working... this fixed the problem)
*Replaced Fan Switch (becuase fan was also not working... this fixed the problem)
*Replaced Coil Packs
*Checked Spark Plugs
*New Oil Filter
*Replaced PCV Valve

What Next?
*Becuase the problem started when a dented oil filter blew and ejected oil over the inlet manifold i'm wondering if this is possible an oil pressure relief valve problem with it only occuring when the oil is cold and thick. Maybe as soon as it thins out the surging stops?

Any ideas from anyone would be really appreciated becuase i feel like i'm banging my head against a brick wall.

Thanks to everyone.

ahrmike

I really doubt oil pressure difference would make an engine surge. It really sounds like a bad ignition or a vacc leak somewhere! Have you tried the vac. leak test trick? Spraying starter fluid near the vacc lines - when the idle changes, you have your leak.

camuman

i vote vac leak. did u ever change the intake mani gasket to hondata one? maybe a bolt loosened up. it sucks too cause that side of the motor is a giant mess. good luck.

nicholasbartleet

Thanks Guys,

Yes, i did do the vac leak test with carb cleaner and nothing. I changed all the vac lines too.

Would this problem persist all the time (not just when totally cold in the morning) if it was a vac leak?

ahrmike

no - my vacc leak on my camaro only occured when it warmed up - oddly enough. If you changed all the vaccum lines, I have no idea.. Maybe you have an electrical gremlin? something losing contact/ground? Bad coilpack? i dunno. sorry im not much more help

nicholasbartleet

Thanks. Well ive checked for a vac leak again with copious amounts of spray and nothing.

I've just removed the rocker cover to check and everything seems absolutely fine under there. The problem persists.

What Next?

I was thinking a new Primary 02 sensor and a new oil pressure switch. I could change the injectors and the coolant temp sensor?

chino101

I would take another look at the air injection system; just a guess based on you saying that it only happens on the first "cold" start of the day. From your mp3 clip, it sounded like the idle surge went away after the air injection pump kicked in. See if it gets worse on really cold days.

good luck

nicholasbartleet

Thanks,
I did disconnect the secondary air system fuze durning an 'episode' and it didn't make a difference but i was going to order one of the Air Pump Delete kits as soon as i can to remove the system and any possibility of it causing a problem.

I suppose in the end i will end up replacing most of the engine before getting rid of this gremlin.

Slows2k

Get a vacuum gauge and hook it up to the brake booster fitting to get a idle vacuum reading.

nicholasbartleet

Thanks Slows2k. I've just phoned all my local garages and they don't have one, so i ordered on off the internet and will test tomorrow.