Transamalley

Hi I have an 83 TA with 305 twin tbi. Since 89. after about 5 hrs running in hotter weather it begins to surge hard shut it off let her cool and its good to go again ...checked most things ...replaced o2 sensor which was the only code comming up. I'm thinking of changing the ecu temp sensor at the front of the inlet manifold ..question I have is has anyone else experienced this and would anyone know the sensor part number ..appreciate any help

sofakingdom

iTrader: (1)

Define "surge hard". Maybe a detailed intelligible description could lead to us understanding what you're asking about.

For things like CTS part #s, rockauto.com, autozone.com, summitracing.com, etc. are your friend. It's a quite common generic part, the same as used on virtually all GM cars of the time.

Transamalley

thanks for the reply bud.
Yeah thanks I looked into the part numbers online as the original has 2 wires that go into a cts that what looks to the naked eye as like a single connector but it's a twin post switch and has been superseded ...now on hard surge ..im looking at idle to 1600 rpm constantly like as if you are throttling it by foot...you can't maintain any rpm by foot and obviously and it won't drive ..so I'm driving along at say 60 cruising for 5 or so hrs then it drops off to idle pull obver and keeps pegging between 750 to 1500 rpm and won't rev much past that in gear ....

sofakingdom

iTrader: (1)

CTSs all have 2 terminals. The early ones had CRAP connectors, later ones are better. Sen - sore guts are the same for all practical purposes; totally compatible, as far as the "message" the ECM gets; just, a more reliable connection. All you need is the later pigtail. In fact alot of the replacement sensors come with it already in the box.

The other, still can't really make heads or tails of it. Get a new CTS and see if that helps. Otherwise, come back, and we'll try to figure it out.

Keep in mind though, that early CFI is well and widely known to be a very difficult thing to ever get right. Not least because, ... well, it's 1970s technology. Thimk back to what you were posting on TikTok with back in 1978 when that control system was introduced. On the bright side though, it's TBI, which means that ANY of the later TBI-ish ECMs will hook right up to it and work, with minor mechanical considerations for the fact that the linkage works 2 TBs instead of just 1. The aftermarket system that RBob on this site makes is probably the best thing you could possibly do for it.

Transamalley

Thanks... you are a gentleman.. its a hobby car and I have others.... its a reco ta and the first car I owned in America.. it only was an issue through long drives through say nevada in summer this girl I haven't road driven for 20 yrs and I'm just going right through it atm replacing what ever I thought might be an issue.... thanks again champ