92Q45 vacuum leak after plenum removal/install?

[jeff33]

I have a 1992 Q45 with TCS.I removed my intake plenum to repair some fuel hoses and injectors(removed injector rails). After putting back together and starting up the Q, i get a high idle (around 2000rpm) along with a "transmission malfunction" on the in-dash display. The idle will not go down below about 1100 until i put it in gear and then is drops to about 800rpm. i never had the high idle or the "transmission malfunction" before.

WHen I drive, the transmission does not like to up-shift when reaching cruising speed. I must let off the accelerator pedal completely and then the transmission will up-shift (3-4 gear) otherwise, I cruise around in 3rd at higher rpms. There does not appear to be any problem in the downshifting.

I am thinking that I have a vacuum leak somewhere and that I must have torn/cracked a hose or missed something when I put it back together (i took it all apart and reassembled but did not find any problems - I have previously removed and re-installed the plenum on 2 other occasions w/o any problems.)

Does anyone know what/which hose(s) the transmission uses to receive a vacuum?

Anyone have any ideas on what could be causing my problem?

I am all ears.

Thanks

Jeff

[Q45tech]

The transmission does NOT use a vacuum reference for anything.............The TPS signal [output voltage] is sent to ecu and tcu in parallel.

2000 rpm is correct intially for a cold start, then it progressive drops to 800 in park over the coolant warmup period [10 minutes].

Read the plenym vacuum after warmup >18" HG.

[skywise6854]

and just a side note there are small coolant hoses wich pass right thru the bottom of the throttle body and im just speculating but perhapse thats affecting the signal the tps is sending ? maybe check to see if fluid is flowing thru they are kinda small and perhapse they became clogged or blocked by something

[Q45tech]

Read idle tps vs coolant temp..................tps should be 0.44 volts at 176F obviously if the hot wax idler cam [fed frm small coolant hoses going in/out of TB] is opening the throttle [warm up] the tps voltage will be higher.

[jeff33]

Thanks for all of the advice, i will check tps signals tonight.

I don't know if it is related to the cold-start routine, as the rpms never go to normal and the rpms are much higher than i have ever experienced befor during cold starts.

Where do I read the TPS output? Do I just unplug the TPS and hook my VOM up to the TPS or do I check cable somewhere else.

Also, I will run the transmission self-diagnostic and let you know what i find.

Thanks

Jeff