I have a '89 F150 Lariat XLT I just purchased , runs good and well maintained , replaced TPS and solved stumbling issue but still have one more :

When started cold it fires up immediately , revs up to about 2K and then stalls , the colder it is the more times I have to restart , max about 3 times for around 40* , each time starts immediately , this morning about 50* and it only took twice , it seems to me it would be a choke related issue , removed and cleaned IAC , already had coil , wires , cap and rotor replaced by previous owner , any ideas or should I just replace the IAC and see what happens at this point , all vacuum lines look good .
Also , once warm it does not do this , and tends to stumble on load a little bit until warm which I would somewhat expect from a manual , once warm all is perfect .

I guess it might help if you know it has a 302 V-8 , there is a new temp sensor that has been installed on the lower intake just below the coolant tube in the throttle body , air filter is clean , fresh gas , pumps ( Frame and tank ) as well as changeover valve also were replaced recently by previous owner , truck was not driven much in its life , only 59K on the vehicle .

 

Have you checked for codes. If you don't have a code reader there's a sticky on here on how to use the jumper wire method.

 

No I have not , have not seen the engine light on at all , runs great except on first start of each day , it is almost like the choke is not working or maybe a fpr possibly , I do have a code reader , will check for codes in just a few minutes and let you know , Thanks for the reply

*I do know the engine light is there as it is visible pre-start

 

I just went out and started it and it started beautifully , maybe the computer needed more time to adjust for the IAC cleaning and the TPS replacement as I have not really driven it but a couple of miles since then .
I went to check the codes and cannot seem to find the connector for the reader , will go and look under the hood for it , maybe it is hiding from me under the dash as well , not sure

 

On this '89 I see no plugs for the code reader under the dash , the block under the hood is empty , nothing there , is it possibly behind a kick panel as opposed to under the dash in the usual place ?

 

Well I just found out that this vehicle has the OBD1 system , so this is why I cannot find the traditional plug , I will have to go and see if I can get the adapter for my code reader for the OBD1 , otherwise I can get the codes via the "flash" method on the dash , will work on this and see what I get .

I am sure I can get the adapter for my code reader as I checked into it long ago but did not do it because I did not have any vehicles that old , go figure , will take code reader back to place I bought it from and see if I can get the adapt or have it ordered , I want the ability to be able to clear the codes .

 

The test port should be by the relay center next to air box. As far as clearing the codes. Unhook the negative cable on the battery for around 15 minutes. The computer can't relearn anything if not done. Unless you get a scan tool/ code reader and do it.

 

Found the test port , all the relay clips are broken as well as the retainer for the OBD1 and the Test connector , they were all there , just laying on the fender well .
I disconnected battery while I was replacing warped rotors , 90 year old German man owned truck , I think he must have rode the brakes seeing calipers are in good shape , pad material was cracked and outside of rotors were black from heat.
After reconnecting everything seems good but have not had a chance to do a cold start again , have to wait until tomorrow , but took it for a 15 minute run and did not see engine light at all , so hopefully it has re-learned and all is ok , will let you know tomorrow .
I did look up my code scanner and there is not a accessory cable for the OBD1 but found a nice walk through using a test light to do it under hood .
I will wait and see what happens in the morning on the cold start and go from there , Thx for the replies , I will give you an update tomorrow .

Guy

 

Hope I can help

 

Having some issues with navigation , could not find my post , but finally found it , amd copying and pasting here that maybe you will find it as I am not getting any comments elsewhere it seems at the moment :

Cold Start Issue/restart issue


'89 F150 5.0 XLT Lariat / Manual 5 spd (OD)

ECM is cleared of codes and no codes have been reloaded .
Still on first start up motor will idle up to 1500 rpm then fall , maybe a little stumbling before cutting off , I can then turn the key again and it will idle up to 1500 rpm and then slowly fall to a smooth idle about 700 rpm just fine ..............the second time.
Also new issue today where motor will not start when hot or run for a bit , can turn off key and re-try and sometimes will fire , most times just have to crank for long periods to get started .
Fuel pumps have been replaced (all of them) , relays are good , they look new as well , tank switch working , tank switchover control was recently replaced as well , also ign coil , cap , rotor , wires and plugs are new.
Before I purchased truck the previous owner had all previous items replaced ( over $1000 ) , have a receipt and confirmed myself .
Have bled fuel rail today , added seafoam for GP , verified fuel filter is new and clean , problem is present regardless of tank selected.
Will chjeck fuel pressure on rail tomorrow to see if possibly FPR , also will try to re-produce issue with not starting and verify I am not loosing spark , the truck only has 60K on it original , the only thing regarding ignition that I know has not been replaced is ignition pick up.
I have personally replaced TPS and cleaned IAC , IAC was not very dirty and from what I understand may be cold start issue but not sure now with this new development which may be the same issue just getting worse.
Outside of taking FPR pressure readings and verifying not losing spark , any other ideas , could it be the IAC and if so is there a way to reliably test IAC , I have priced it and it is $70 , pretty pricey .