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6G Celicas Forums > 6th Generation Celica > Engine/Transmission/Maintenance
wvuguy
I swaped 7AFE in my 94 celica ST. Now the only way to start is to spray some throttle body cleaner in intake and it starts right up. I changed the fuel filter, verified there is spark when cranking and fuel injectors fire. Changed out the temperature sensor. Double checked all wiring and vacuume lines.
One thing is noticed is once the engine is running, the rpm will flicker if I turn the headlights on. Also If I put the car in drive, it shuts down. It will run in reverse though.
Any idea? thanks.
stwin2
check ur fuel pump and the injector gaskets
rave2n
What all did you swap?

Block,Head, accessories, sensors?

I would start with checking your fuel pressure, sounds like its to low.
wvuguy
Fuel pump was running fine 15 days back with the old engine. The engine had a knock but used to start right up. You mean injector O rings? One thing different in this engine is that its federal model so there is no EGR. So couple EGR wires are not connected to anything.
wvuguy
The new engine came with the intake manifold (including injectors). I used the wiring harness and accessories from the old engine including power steering pump, alternator, ac compressor. The header was different so I used that from the old one too (no oxygen sensor in the new one). The engine is from a 93 corolla so it does not have a crank sensor and neither did my old one.
rave2n
Should be fine with EGR delete, atleast mine was when I capped it off when troubleshooting. That being a OBDI 94 7afe.

You need to use your intake manifold from your old 7a, the corolla one won't work from what I understand.
wvuguy
The new engine came only came with intake manifold and injectors and all sensors in the block such as oil pressure, coolant etc. Rest of the stuff like MAP and MAF sensors are from the old engine.
rave2n
Ugh, might need a expert to help ya then~!

Did you try your old injectors and rail?

There are quite a few controls on the intake manifold itself, such as the TPS, EGR, etc etc...

To me, it seems the issue lays there in the manifold itself somewhere...can't pinpoint for ya at the moment =/
wvuguy
Not yet but thats a good idea. I am going to try that this evening.
rave2n
QUOTE (wvuguy @ Apr 5, 2011 - 4:13 PM) *
Not yet but thats a good idea. I am going to try that this evening.


GL! Let me know how it goes, curious now.
wvuguy
QUOTE (rave2n @ Apr 5, 2011 - 5:09 PM) *
Ugh, might need a expert to help ya then~!

Did you try your old injectors and rail?

There are quite a few controls on the intake manifold itself, such as the TPS, EGR, etc etc...

To me, it seems the issue lays there in the manifold itself somewhere...can't pinpoint for ya at the moment =/


I wanted to swap the intake manifold but one of the EGR pipe goes into a hole in the block which this engine I got does not have which is why I did not swap it. I will swap the fuel rail and let you know what that does.
wvuguy
I ended up replacing the fuel pressure regular only since the rail looks exactly the same and I got too lazy lol. Looks like you have to take out the throttle body and top cover of intake to get the fuel rail out. Well that did not work. I took off the distributor cap and there is a notch on the distributor rotor at the contact point. It looks damaged. I will change it out tomorrow and see what it does.
rave2n
QUOTE (wvuguy @ Apr 5, 2011 - 10:11 PM) *
I ended up replacing the fuel pressure regular only since the rail looks exactly the same and I got too lazy lol. Looks like you have to take out the throttle body and top cover of intake to get the fuel rail out. Well that did not work. I took off the distributor cap and there is a notch on the distributor rotor at the contact point. It looks damaged. I will change it out tomorrow and see what it does.


Hmm, timing was where I was going to with it next if it wasn't something on the manifold.
wvuguy
I have checked the timing over and over again. As for the crank timing, when the notch on the crankshaft pully is at 0, the cam pully hole lines up with the bearing mark. I have pointed the distrubutor cap at plug#1 at this point. If new distributor cap and and rotor does not solve the problem, I will swap the intake manifold. How did you end up bypassing the EGR? The intake manifold from the old engine should fit except for a a hole in the block for a metal pipe which I believe is for exhaust recirculation.
rave2n
I never completely bypassed the EGR in sense of not throwing a code. I simply let it throw a code to see if the car would function diffrently.

I just took a thin piece of metal and replaced the valve over top of it to stop the flow of gases.

If your block does not have the hole for the EGR pipe, I cannot see it hurting you to remove it. You have to jump 2 wires on some sensor to stop it from throwing a code, I cannot remember which ones. Might have a hard time finding that info, being its a debate on here wheather to remove the EGR or not. Either way, just find a plate of some sort to bolt off the where the EGR module plugs into the intake manifold.
wvuguy
Thanks rave2n. I am gonna do that once I swap the manifold. I just put new NGK plus and wires, new dist cap and rotor. Still needs a spray in intake to start but idles very smooth now. While it was on I hit the OD button on shifter and it bogged down and turned off. I am leaning towards an electrical problem or short.
rave2n
QUOTE (wvuguy @ Apr 6, 2011 - 2:23 PM) *
Thanks rave2n. I am gonna do that once I swap the manifold. I just put new NGK plus and wires, new dist cap and rotor. Still needs a spray in intake to start but idles very smooth now. While it was on I hit the OD button on shifter and it bogged down and turned off. I am leaning towards an electrical problem or short.


See I don't think its electrical because you have spark. The car can run and idle.

The reason I think its something on the manifold, not actually the manifold itself, is because there are many controls on the manifold. You can most likely use the new manifold, but swap out all the components off the old one. I cant recall everything that resides on the manifold, but I know its quite a bit.

Have you tried resetting your ECU just for S&Gs?

When I had a problem simliar to this, it was the distributor itself was shot, which is why I said timing earlier, but you've confirmed that is correct, which is why I fall back on some sort of sensor or control on the manifold, being you said you used the new one. Now you said you used the old MAF sensor, but that resides on the firewall so I expected that =)

We know its got fuel, or it wouldn't run, we know it has spark, or it would start at all. Originally I thought it was not enough fuel, but now it would appear the fuel/air is getting where it needs to, just not correctly, which is why I feel its something from that new manifold.


Was this 7a out of a Corolla?
wvuguy
I have disconnected the battery a few times so I would think it would reset the ECU. Yes this engine was out of a 93 corolla. The only two sensors I know of in the intake is the TPS and IACV sensor. I can swap those out. I double checked for ground problem. When the car is running, the battery terminals show 14 volts and there is less than .02 voltage between engine block and negative battery terminal so seems like engine is grounded fine.
Well I observed the behavior again today. As soon as I hit the over drive button, the car starts to bog down and the the temperature gauge goes all the way to max. So some kind of electical issue there. Also when I put the car in drive, and hit gas the speed goes up but the transmission does not shift. Essentially it stays in 1st gear (I dont have the wheels on and the car is on jack).
rave2n
You really gota change out to your original manifold, controls and sensors before we can troubleshoot further. I don't think its electrical, but I cannot say it is or isn't with that new manifold on there.

And just so we are for sure, goto autozone or something and rent the kit to check your fuel line pressure, attach where the filter is, to the rail, or the rail itself if it has the adapters, and compare pressue with specs. You get your money back when your return it =)
wvuguy
I changed out the throttle body today which has all the sensors from the old engine but the same problem. I agree with you, I am gonna change the complete intake header this evening and see what it does. And thanks for the tip about the fuel pressure. I am gonna get that too and check it out. Also the gas in the car is a year old so it might be no good. Some how the old engine was running on it though. I nothing works, I am gonna drain the gas and put fresh in. Thanks for the help!
rave2n
Cool, no problem.

Double check the injectors seating and seals when you swap out.
wvuguy
I rented the fuel pressure testing kit from autozone but the brass fittting snapped when I was trying to tighten it up, so could not test the fuel pressure. By the way the fuel looks almost orange color so it definately needs to be changed out.
As far as the swapping the intake, since I had the old one a apart, I decided to clean it up since it was full of carbon. Got it assembled back together but didn't get a chance to swap it yet.
wvuguy
Found some time to take the intake out. While at it, I found the ground above starter coming from the wiring harness loose. It was hardly touching the block. That could explain the weird electric behavior. Gonna put every thing back after work and see what happens.
wvuguy
Fixed! Had to take the starter out to tighten up the gound wire. Put manifold from the old engine and she started right up. When I turned the key to on position, one thing I noticed right away was that the temperature gage was all the way to cold instead of a little up it used to be even when the car was cold. In reverse, transmission used to move forward. Engine would turn off in drive. Now if the manifold fixed the start up problem or the ground fixed it, that I am not sure about but a missing ground connection was causing some weird things to happen.Thanks for the help.
rave2n
Combo of both in my opinion.

I don't think a bad ground could do all that, but certainly contributed to the problem. All those damn controls on the manifold, important!

Glad it works, good work!

If it helps any, your my first start to finish troubleshoot thats worked in the end!
wvuguy
lol thats awesome. Learn some thing every day.
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