4AGE not running right, help is appreciated

subiedrake
Posts: 6
Joined: Sat Mar 26, 2016 12:42 am

4AGE not running right, help is appreciated

Postby subiedrake » Tue Nov 01, 2016 8:52 pm

Alright guys what's up, I've done all my best and still can't figure out what's going on. So here's the details.

SR5 w/ 4AGE swap
-Stock ecu
-External pump
-allegedly has tomei pon cams
-other than that its stock


So upon cold start up it starts everytime but wants to die, the engine idles very shakey, almost as if it's running on 3 cylinders, but I don't think it is. Runs like garbage until it's hot. Once it's hot it'll drive decent. Suuuuper slow, slower than my old 4ac. But I drove it for over an hour and it was fine. So the other day I messed with the timing and MAF preload and it now runs aloooot better but I know it's not how it's supposed to be. Also when taking off very slowly or when the pedal is only slightly tipped in, the car acts like it hits a dead spot in the map, or it cuts fuel or spark, the car bucks like crazy. But under full load it pulls decent. I blind timed it, as my timing gun could not get a reading for unknown reasons. Yes I did short the check connector. I'm willing to pay some one to diagnose my car, I just don't have the time or patience. I'm located in Whittier, CA. Any help of input is much appreciated.

SgtRauksauff
Club4AG Enthusiast
Posts: 113
Joined: Mon Jan 14, 2013 9:43 pm

Re: 4AGE not running right, help is appreciated

Postby SgtRauksauff » Wed Nov 02, 2016 9:08 am

did you get the car as it sits right now?

If it were me, knowing that the engine had been opened up, and not knowing if it ever ran correctly for the previous owner, at a MINIMUM, I would yank the cam covers, make sure the cam timing is correct (timing belt), make sure the distributor timing is correct. Make sure the spark plugs are connected with the correct firing order, and make sure there aren't any vacuum leaks. I would also get a fuel pressure gauge to make sure you're getting the right amount of fuel, maybe even an AFPR to adjust it if need be.

If the problem exists only when cold, it could be the idle air circuit, which normally is fed by coolant, and a plunger is actuated by wax expansion.

but if the thing is slower than a 4AC, I think there is a serious problem with timing, that's what jumps out at me.

--sarge

Deuce Cam
Posts: 1346
Joined: Sun Jan 13, 2013 2:41 pm
Location: AZ

Re: 4AGE not running right, help is appreciated

Postby Deuce Cam » Wed Nov 02, 2016 10:17 am

Did you check for cel/codes? Most seem to throw code 11/tps (unless previously serviced) which doesn't allow the ecu into diagnostic mode, and thus, you won't be able to set the timing as per the service manual. However, you can use a timing light to see if ignition is at 16* btdc - without the the diagnostic port jumped - to quickly see where you are at.

notnilc20
Club4AG Pro
Posts: 575
Joined: Sun Dec 27, 2015 7:56 pm
Location: Memphis

Re: 4AGE not running right, help is appreciated

Postby notnilc20 » Wed Nov 02, 2016 10:38 pm

Deuce Cam wrote:Did you check for cel/codes? Most seem to throw code 11/tps (unless previously serviced) which doesn't allow the ecu into diagnostic mode, and thus, you won't be able to set the timing as per the service manual. However, you can use a timing light to see if ignition is at 16* btdc - without the the diagnostic port jumped - to quickly see where you are at.

This is correct.....I had similar symptoms as OP when i just adjusted timing by sound.....but then I set the timing with timing light to 16deg. Btdc and the car revs great and doesn't have any issues of wanting to die after cold start up. I also had that bog when applying slight throttle....no more after timing properly set. Mine was throwing code 11 too so I just set timing without diag. Plug jumped, Like Deuce cam said. Runs like a top now.

User avatar
Jeonsah
Club4AG Expert
Posts: 455
Joined: Wed Jan 09, 2013 10:44 pm

Re: 4AGE not running right, help is appreciated

Postby Jeonsah » Tue Nov 08, 2016 7:13 am

Start with a compression test and then check for spark.

Ultimx
Club4AG Enthusiast
Posts: 84
Joined: Thu Jan 10, 2013 10:46 pm

Re: 4AGE not running right, help is appreciated

Postby Ultimx » Tue Nov 08, 2016 7:51 am

Rent a timing gun and make sure timing on the cams, crank, and dist. are set correctly. Check for codes and clear them all before moving onto timing.

User avatar
SR85DET
Club4AG Enthusiast
Posts: 132
Joined: Sat Feb 16, 2013 7:16 am

Re: 4AGE not running right, help is appreciated

Postby SR85DET » Tue Nov 15, 2016 6:24 am

Both time and patience are needed with these cars. As others have stated, cam timing may be off. Check compression as well, who knows if the P.O. put the cams in correctly or checked valve lash. Could be mechanical, could be electronic. If you were in Ohio I would help you out :/