Throttle body lag time

[gmbadgley]

Does anyone have any ideas if this is normal?
02 tundra 4.7 V8. I have a 2-3 second delay in displaying any throttle change when in the TPS % through the OBD connector.

The intermittent problem is at around 30, under light acceleration it may fall flat on it's face for a second and then recover with no problem. It has never displayed a code.

I'm borrowing a used Modis from my dealer so I'm a little out of my comfort zone here.

thanks Greg

[greasybob]

I would back probe the TPS and APP sensors and check with a scope (voltage over time) while doing a sweep check.

[Witsend]

Well if you are viewing the complete list of Pids on something like an old MT2500 I know the data refresh rate is very slow for the data, and if you are using an old used gen 1 Modis it might not be all that much faster. I would try to view and graph the 2 pids to see if the delay is reduced, and of course verify the grounds are good at both sides of the rear of the engine before condemning anything. Any codes for anything?

[Flatrater]

Does anyone have any ideas if this is normal?
02 tundra 4.7 V8. I have a 2-3 second delay in displaying any throttle change when in the TPS % through the OBD connector.

The intermittent problem is at around 30, under light acceleration it may fall flat on it's face for a second and then recover with no problem. It has never displayed a code.

Yes, it would be quite normal especially when the tool you are using cannot take advantage of the fastest access to the data stream or if the particular vehicle has a slow data stream. It only gets worse if you have selected too many pids. (not all systems are affected this way)

This is not the way to find an ETC fault, the ECM is monitoring the circuits much faster than the data stream is updated. If you have no ETC code, I wouldn't be concerned with it (the ETC system).

What I would do with the data stream is pick out the PIDs that are likely to help you. Consider what can cause the concern you're dealing with. Ask yourself what does an engine need to produce power and what can take it away. Those PIDs should be helpful.

[diesel71]

record the data with the modis, go on a test drive and let it fall on its face while recording. then use the modis or better yet shop stream connect and look for the fault.

[Crusty]

record the data with the modis, go on a test drive and let it fall on its face while recording. then use the modis or better yet shop stream connect and look for the fault.

AGREED-!!
Much easier to view the entire recording, AND zoom in, then cull out PIDs "editing" the data pid list, narrowing things down to find the "event" that indicates the root cause.
.