Fresh rebuilt 20V engine, 3-4K rpm on idle and code 41 (TPS)

[onnaj]

Hi,

I've almost completed my blacktop swap, but i'm struggling with the last parts.

Starting isn't a problem at all, i turn the key and it start right away. In the beginning there was some blue smoke (that was scary) but that disappeared very quick. The smell of the coated header won't haha

When first starting the check engine light was on right away. The engine wasn't running really bad though, even while i capped some wrong vacuum lines and forgot to connect the MAP vacuum. :S Did a check 3 times and still forgot something.

But to continue......At first it gave 4 codes or so, 1 was my own fault (MAP not connected), 1 is the IAT which i haven't connected, but my old 7AFE ran fine without it. The other 2 were code 31 (map) and 41 (TPS). Code 31 i have solved, think the connector on the ecu was just a bit loose, but code 41 resist

I meausered the resistance between the cables and they all go to the ecu without resistance.

I decided to change the tps with the tps from my 7AFE. It looks different from the inside but i did want to give it a try. Since then the RPM goes way up at idle about 3-4k rpm! That isn't nice for a cold just rebuilt engine without any mileage.

So i decided to use the old tps again, but then again the same problems. I cleared the ECU memory and put my 7AFE tps back in.

Yes, code disappeared....shortly. But idling was very high. That high it didn't dare to keep it running for some mintues to adjust the timing with the timing light.

Do you guys know what can be wrong. I don't think it's a timing thing, cuase when i turn the distributor it won't change the rpm.

Could the TPS gone bad? Are they interchangable? Hope someone can help me out here cause i need the car in the weekend.

Thanks!

[onnaj]

Today the code was still gone with the 7AFE TPS, but the high ilde is still there. But when i first started her up this morning the idle was fine (about 1750 rpm, but that's normal i think for a cold 4AGE engine) but after a minute or 2 the idle speed went up high again. After i pushed the thorttle a bit the rpm went even higher to 4000 rpm.

I then decided to disconnect the ISCV connector, but that hadn't any consequences for my ildle speed at all. I think the ISCV isn't doing much yet, while the aircon compressor hasn't a belt on it, the blower/defogger/electric fan/cooling fan 2/etc relays aren't connected to the ECU. Or is it always working?

Okay, next step...i decided to disconnect the tps connector and now the RPM got even higher then 4K! I almost don't dare to start her up again. Afraid of damaging the new engine

Yesterday the catalytic convertor and the end of the exhaust where completely red! I think by excessive fuel and ofcourse oil remnants.

All the new spark plugs were black btw, a sign of over fueling i think.This is an example of how mines look:

Can the igniter also cause this sort of problems?

Hope someone can help me out here quick, cause i need the car. Thanks folks!

[onnaj]

I solved the very high idle problem. As simple as it could be. The TB's didn't completely close, though i though it was. We did put our hand in front of them and then we noticed our hands were sucked in, came in between the camshaft en valves and got out through the exhaust
Okay, no they were completely sucked in, but we felt the sucking very obvious.

Now we've adjusted the throttle cable and then the RPM was normal again.

But after a drive, yes my first drive with the new engine, the idle speed went up a little again. Now it's idling @ 1600 rpm. Still got the TPS error, so i've ended up with ordering a new one. Hopefully it is in before the weekend. The price didn't scare me, about $120. Still a lot, but i'd expected a lot more.

[Army Fork]

A new engine may idle a little higher too, not entirely sure but if you consider the ring and bearing wear-in period, it may naturally idle higher to avoid stalling. That said that should disappear after your break-in drive.