Chipsterle

Hello all, newbie here glad to find such a wonderful informative lexus forum...

Now on to my problem. I have a 95 es300 that developed a rod knock so I decided on replacing the engine with a used one. I found a guy with a toyota 1mz-fe not sure what exact year for sale on facebook marketplace for a decent price. I purchased and took it to my local mechanic for a engine swap. The only differences were he had to use my fuel rail and intake from my engine and my power steering pump from my engine. Also there was no oil sensor plug on the bottom of the engine and he had to use my coil packs as the toyota engine had just regular spark plug wires.After getting it to crank and run for about 15mins we shut it down and it would not immediately crank back up. After changing crank and cam sensors still no crank so eventually we checked the plugs and they were wet with gas. After changing plugs it started back up and after shutting off again once again no crank. The mechanic seems to think a difference in the fuel rails or the fuel pressure regulator is the problem as my lexus fuel rail has a fuel pressure regulator and the the toyota fuel rail did not have a fuel pressure regulator built onto it. he seems to think that now the car is shooting too much gas and is fouling the plugs. Do any of you guys have any insight or pointers on what we should be checking or anything else we may be diagnosing wrong?

Thanks and any help will be greatly appreciated..

LeX2K

Any time an engine swap is done unless the donor engine is the same all accessories from the original engine must be transferred to the replacement. If this isn't done you're doing an experiment on what is compatible and what is not.

Seeing you don't know the year of the replacement engine I don't know what kind of advice I can give you. To be blunt your mechanic should know better than to try and mix and match parts.

Chipsterle

All accessories such as starter alternator ac codensor etc were transferred I just didnt mention that because that was common knowledge. All of my harness connectors plugged into installed engine with the exception of the oil sensor plug. Was just wondering what could be causing the plug fouling..

Arsenii

Hello,
What do you mean by that?
Are you sure that you've got a correct engine? 1991-1996 Lexus ES300 and Toyota Camry came with 3VZ-FE (older) and 1MZ-FE engines. What was installed, and what did you get?

Hope this helps and best of luck!

Chipsterle

I have a 1mz engine and this is also a 1mz engine to be installed.... What I meant by the spark plug wires was it connects to the coil by spark plug wires and not wire connectors as my lexus does...

LeX2K

I think sometime in 1995 there was a change from coil on plug to the waste spark (3 coils 3 wires). But that doesn't matter you need to use ALL the original accessories, original ECU, coils, intake. Everything means everything.

Chipsterle

All the original accessories from my vehicle or from the toyota motor? We swapped my lexus accessories to the toyota motor and also the fuel rail egr valve intake plenum and coil packs. We are also using the lexus ecm..

LeX2K

Your vehicle, you keep the engine itself nothing else. Manifolds, vacuum lines, harness, fuel components, ECU. Everything means everything! Since the ECU is dumping fuel look at live data with a scan tool, or the engine is not running at all?

Chipsterle

Yes the engine has ran. After install it ran rough at 1st but eventually smoothed out and ran for 30 minutes or so. After shutting off it would not crank. After inspecting the plugs they were wet with gas. After installing new plugs car fired right up but shut down again after about 5 minutes. No check engine lights are read with a scanner.. Also see where the lexus fuel rail has a pressure regulator attached and the toyota fuel rail does not. We used the lexus rail but are going to replace the regulator to see if its the cause of the problem.Will have to check live data after a install of new plugs again.

LeX2K

Does the regulator have a vacuum line on it? If so a bad one will dump fuel into the intake.

Chipsterle

Yes the regulator has a vacuum line on it will inspect later... Would a bad o2 sensor cause excess fuel to be dumped on the plugs also?

LeX2K

Not sure, doesn't seem like it could to the extent where you have raw gas on the plugs maybe I'm wrong. Unplug the sensor to find out this will put the ECU in guess mode which won't go overkill with fuel trims.

Chipsterle

Changed the fuel pressure regulator and now the car cranks and runs everytime it is started. But it has the codes p0300, p0301, p0303 and p0305.... Tried unplugging the connectors to the coils and the engine idle does not change as the coil connector is unplugged. Have ordered new coils but its hard for me to believe all 3 rear coils would fail at the same time. If anybody has any input would appreciate... Thanks..

FobLexus

The rear plugs or coils might have fuel that sprayed into them similar to the first time you said this issue occurred. If I were you I would check the ECU. I've seen this issue before where the car sprayed too much fuel and it was because of a bad ECU. Are you using the ECU from the old engine or the new one? Do you know if the ECU from the new one is any good?

Chipsterle

We are using the ecu from the old engine, did not obtain the ECU from the replacement engine...Plan on swapping coils on cylinders 1,3,5 in the next day or so. How can the ECU be checked to see if it has issues?