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View Full Version : CA18DET HELP! Bogging down during throttle


matt87
01-28-2007, 02:00 PM
I have a s13 with a ca18det. It is hooked up to a safc with a rich safetune. It has trouble idling and driving. When too much throttle is added it will bog down and misfire until you take your foot off the gas. It will misfire while underlight throttle and idle as well. Also, while on the highway, it has trouble staying up to speed while going slightly uphill. It just seems like the engine runs out of steam. I know that it is not the engine running rich causing this problem becasue no matter how the safc is adjusted, it still runs the same even when leaning it out. Could it be the timing? How is timing adjusted on the ca18det? Someone told me to adjust the cam sensor. Sorry for the lack of knowledge on the engine but any help would be appriciated.

shane_lxi
01-28-2007, 02:05 PM
Try replacing your mafs. My car did something like this a few weeks ago. Replaced the mafs, and no problems.

matt87
01-28-2007, 02:41 PM
The car does have a 300zx maf. I rewired it when i got this car becasue the wiring was crap and i volt tested it when it was out. It seemed to be in good working order. I can try to start the car with it unplugged to see if it changes it but im pretty sure it will. However, if it doesnt change i guess then it could be the maf or my wiring or even the wiring of whoever did the swap.

matt87
01-28-2007, 02:47 PM
Well, the car started but it ran very ruff so it doesnt seem to be the maf.

~Split~
01-28-2007, 02:59 PM
ok there could be 3 problems. took me a while to figure this one out. but let me ask you when was the last time u changed the oil? and how cold is it out where u are from?

1.needs oil change and lighter oil could help

2. Maf sensor could be going bad

3. timing could be off or the chain is going bad.

matt87
01-28-2007, 03:05 PM
Well, it doesnt seem to be the maf. I could try changing the oil. It is currently 10-20 degrees F but it is acting the same as it did during the fall 60-70 degree weather. I could check the timing as well, which is what it seems to be boiling down to. How is spark advanced or retarded on the ca18det?

~Split~
01-28-2007, 03:09 PM
i can read up on it for you. because i do know it did the same thing on my CA in my hatch and i changed the oil and it got better but the weather was in the 70's and it was near winter.:tweak: but then again the timing chain started going bad so thats your last solution is to look at that. but the timing advancing on a CA is kinda weird.:loco: but let me look up for you man.

Split

~Split~
01-28-2007, 03:25 PM
its hard to say but check you belt maybe it could be missing a tooth.

boosteds13
01-28-2007, 05:28 PM
Base timing should be set at 15* BTDC.

idiot goes sideways
01-29-2007, 07:00 AM
3. timing could be off or the chain is going bad.


chain?:keke:
the CA hasn`t such a "shit" valvetrain like KA/SR

sorry to interupt!

idiot goes sideways
01-29-2007, 07:19 AM
you checked the AFM.........ok
check yor air fuel
check ignition timing, spark plugs, coils
check water temp. sensor (probaly not the issue but anyway)

to me it sounds more like your air fuel isnt right, not the ignition
maybe your safc make problems

boosteds13
01-29-2007, 09:24 AM
chain?:keke:
the CA hasn`t such a "shit" valvetrain like KA/SR

sorry to interupt!

Before you go running your mouth, please realize the CA and KA valvetrain is nearly identical. Both use cam-on-bucket design.

matt87
01-29-2007, 12:44 PM
How is ignition timing adjusted on the ca?

boosteds13
01-29-2007, 01:56 PM
How is ignition timing adjusted on the ca?

Use the loop at the back of the coil pack subharness... wait for the car to reach normal operating temp. Loosen the bolts holding the cam angle sensor. Point the timing light at the crank. The marks on the crank pulley from left to right are 5*ATDC, 0*, 5*BTDC, 10*BTDC, 15*BTDC, 20*BTDC. Turn the CAS ever so slightly until you have it dead on at 15*. Then tighten the bolts. If the timing is PHYSICALLY off (meaning jumped a tooth), then the belt needs to come off and the marks need to all be manually realigned.