HELP!! 99' 10AE extended cranking(hard to start) only when engine is cold

[Rotaku]

Hi guys,

I'm a new owner of a 99' 10AE NB which I've purchased about 4 weeks ago.
Used to drive FD as a daily, had to purchase another daily since FD went into heavy mods, stripped down.

Pretty long story, but it all started with alternator failure on the way back to home (NJ) from Florida right after purchase. I had to pull it over to nearby gas station, went to autozone, bought an alternator & swapped. It ran fine till I got home, but then it started to stall randomly at the stop from the day 2.

It threw some codes about Cat converter, so I've removed cat, installed "mini cat" o2 fouler, then the code went away. But since the problem remained same, I've changed plugs, changed CAS(Crank Angle Sensor) and then finally fixed stalling issue by cleaning up the IAC valve & TB, replacing TB gasket.

It ran fine for next couple days. Now, all of sudden it doesn't want to start when engine is cold (no matter of outside temp, it starts right away & runs fine when its fully warmed up). I have to crank it for at least 3~4 seconds. Once it fires up, it sputters until I give bit of gas. Once it enters IDLE stage, it idles fine. Also, idle droops at the release of gas if I drive the car without fully warmed up, it drops as low as 400 but doesn't stall at least.

Anybody has any clue on this problem?
I ordered fuel pump in case of if there is any clogging or malfunctioning in fuel system, I want to know if anyone has some kind of checkpoint lists to narrow down the problem more accurately.


Currently, car condition is

1. Extended cracking on cold start (3~4 secs, need bit of gas to make it start idle correctly when it fires up first time, usually happens after when car has been parked more than 4 hours.)

2. Idle droops when gas is released, when car is driven before it gets fully warmed up. BUT It doesn't droop anymore once the car is fully warmed up.

3. Car runs way fine when it gets fully warmed up. it also starts right away if engine is already warmed up.

4. I THINK I am smelling bit of coolant while driving, sometimes don't.



Tried few things on my own,

1. manually pressurizing fuel system before first crank (key ON, stay, OFF, repeat for like 3 times), didn't work.

2. de-flooding by giving full gas while turning the key. (IT KINDA WORKED. after cranking for 2~3 seconds with fuel-cut, and OFF and then ON, it started right away few times.)

3. checking a Vac leak, I couldn't find anything else with my bare ears except TB gasket.


Thanks for reading, sorry for having some grammar issue here and there.
I would really appreciate if someone can help me to get out of this never-ending loop.

I've searched and searched about this problem, there was just too many assumptions I couldn't try everything.
Some said it might be leaky injectors, some said vac leak, some said bad MAF, some said IACV still bad, some said EGR, some said gasket, some said coil pack, on and on and on..
Which one should I try first..?

One thing that confuses me to hell.. can all these above issues can cause hard start & idle droop(only at stop, not a rough idle) ONLY when engine is cold? car just runs way too fine once it gets warmed up.

help meeeeee guys

[kung fu jesus]

A lot of the recommendations you received are pretty easy diagnostics. A multimeter and a factory service manual (FSM) are your ticket to narrowing down your list.

There is a complete FSM on the Internet in PDF form. I saw it when I pulled down the one for my '92. I am on my phone, so searching for that site is a little difficult at the moment.

I also had a 10ae with a number of issues. The FSM that came with the car was ESSENTIAL to finding the root of the issues I had with fouling cats, AC issues, and a few other problems.

I know it isn't the answer you were probably looking for, but the shotgun approach of throwing parts at it is frustrating, expensive, and rarely solves the issue for long.

I can tell you I spent waaaay too much money on cats and too much time cleaning emissions equipment only to find out a 20 minute diagnostic on the coilpack concluded in a final result. The FSM gave clear steps and data to compare and troubleshoot.

Good luck!

[mx54life]

I would assume you checked and reset the timing on this baby after you dealt with the CAS?

[Rotaku]

@mx54life
I have read somewhere saying 99 timing cannot be reset, since its using VVT & knock sensor. I did idle speed adjustment with TEN & GND grounded, right after I replaced CAS and TB gasket replacement, it made car lot smoother & no idle droop after warmed up but didnt fix cold start & idle droop at cold engine :(

[Rotaku]

@kung fu jesus
Thanks for an advice! I will go through FSM, hope i can find a solution here :)